InAs/Ga(In)Sb type-II superlattice infrared detectors based on mature III-V material and devices technology has lots of advantages such as tunable energy structure and wide response wavelength range, low dark current and high performance under high temperature, etc. It has been chosen as the Third-Generation infrared detector and developed rapidly in recent ten years. In this paper both theoretical and experimental study have been performed to indicate high temperature operation characterization for the InAs/Ga(In)Sb type-II superlattice middle wavelength infrared detectors . Photo-generated carriers, the ratio of photo conductance and dark conductance were calculated by balance equation method. The dependence of I-V, optical response, device detectivity on temperature has been tested and studied to disclose temperature characteristic of the InAs/Ga(In)Sb type-II superlattice infrared detectors. The results verify the middle wavelength InAs/Ga(In)Sb type-II superlattice infrared detectors can operate at high temperature with high performance.

The short wavelength infrared (SWIR) band near 1.0-3.0μm plays an important role in many applications such as weather forecast, earth environmental or resource observation, low light level systems and astronomical observation. It is well known that InGaAs detectors can shift the cutoff wavelength from 1.7μm to 2.5μm with the higher fraction of indium in the ternary In_XGa_1-XAs material grown on InP, which results to material defects and poorer device characteristics due to the lattice mismatch. Dark current characteristics of extended wavelength InGaAs detectors were investigated in this paper. Dark current mechanisms for extended InGaAs detectors with different absorption layer parameters and device fabrication process were analyzed according to current-voltage curves at different temperatures and bias voltages. Activation energy of devices was extracted from current-voltage curves. Activation energy is related with absorption layer concentration and test temperature. Activation energy is the higher for the devices with the higher absorption layer concentration at lower bias voltage at the same temperature range, which shows that the narrower width of the depletion layer in the devices results to the lower generation-recombination current. The devices with the optimized etching and passivation parameters show higher thermal activation energy and the lower dark current. Dark current mechanisms of the ones are dominated by diffusion current at the higher temperature and lower bias voltage, whereas dominated by internal generation-recombination current and ohmic leakage current at the lower temperature.

This paper presents the progress in the cadmium zinc telluride (CdZnTe) single crystal growth and high quality CdZnTe substrates fabrication at Shanghai Institute of Technical Physics (SITP). The 60 mm diameter ingots with almost 90% single-crystals were grown by the vertical Bridgman technique. The average single-crystal yield of all ingots grown in the last two years was about 60%. The large-size substrates (> 40 × 60 mm²) were obtained. The processing and assessment of CdZnTe substrates were introduced. Especially, the sliced wafers were etched by the bromine-methanol to remove slicing damage rather than by lapping and polishing. An Olympus BX51-IR transmission microscope with mapping function was employed to take images of the inclusions/precipitates in the full wafer and the surface of the wafers etched by the Evenson etchant. The inclusions with different shapes were investigated. The inclusions and precipitates were distinguished. The inclusions occurred at the crystal growth stage and the precipitates were separated from the nonstoichiometric crystals at the cooling stage. The both inclusions and precipitates mainly originated from the nonstoichiometric CdZnTe source materials. The mosaic structure of the etch pits profiles in the substrates has been eliminated. The etch pit density (EPD) of CdZnTe substrates was counted by the software and the average value of EPDs was less than 5 × 10⁴ cm^-2. After the defects of the substrates were measured, the substrates were polished. The surface flatness and roughness of the substrates were also improved by optimizing the technology.

Thermal infrared imaging from geostationary satellite can provide all time, real time and video observation, and it can achieve fast pointing and information acquisition of any object on the earth disk. It is more suitable for timely information acquisition of emergent event such as natural disaster. The paper introduces the development and related applications of GEO thermal infrared imaging technologies during the past several decades. It then introduces a concept of all time, real time and video observation from GEO using two thermal infrared staring imagers with different spatial resolution and field of view (FOV). The low spatial resolution and wide FOV thermal infrared staring imager is used to monitor objects within a large area concerned, while the high spatial resolution and narrow FOV thermal infrared staring imager is used to acquire detailed information of the interesting objects within a small area. The main characteristics and technical solutions about the proposed concept are described in the paper.

Detector MTF based micro-scanning image reconstruction (dMTF-MSIR) algorithm was presented to reduce image blur due to spatial integration degradation effect (SIDE) of focal plane detector. Firstly, a high-resolution oversampling image was generated from four successive frames in micro-scanning image sequence using inter-frame difference oversampling reconstruction (IFDOR) algorithm, in which case the required inherent inter-frame offsets were obtained by calibration. Secondly, a Wiener filter was built based on the SIDE model characterizing the image blur due to spatial integration of radiation intensity distribution at sensor cell surface. Finally, a high-resolution reconstructed image was generated by processing the oversampling image using the Wiener filter to reduce image blur due to SIDE. Simulation results showed that if spatial sampling frequency of focal plane detector was fixed and micro-scanning images were noise-free, the loss of reconstructed image detail increased with the increase of duty cycle of detector. However the influence of duty cycle of detector was gradually exceeded by that of image noise with the increase in image noise level, and in this case suppressing image noise should be given priority. Furthermore, the performance of the presented method was restricted by aliasing, so imaging light path should introduce an optical low-pass filter with the cutoff frequency that is less than or equal to twice as large as Nyquist sampling frequency of detector. The experiment based on infrared images of actual scene showed that reconstructed images generated by the presented method had a higher image contrast and sharpness than that of IFDOR algorithm.

During the runtime of the spacecraft in space, spacecraft uses optical navigation sensor to capture and measure its flight attitude information.Very high accuracy star sensor is a kind of navigation sensors.Star simulator serves as the calibration equipment for star sensor on the ground has received more and more attention.In order to complete the testing of very high star sensor, according to the working principlestatic of the star simulator,an collimating optical system has been designed which can achieve high precision simulation of the star point.Using ZEMAX software to complete the design of the optical system and calculating the star point emitting precision at -45 °C ~ +65 °C with multiple structural function.The design results show that,the designed wavelength of the system is 500~900nm,wherein the center wavelength is 680nm.At 20°C,the distortion is 0.01%, MTF is higher than 0.5 at the frequency of 60 lp/mm within the filed of view of 7.2°.The collimation errors are both less than 1″ at the two limit temperatures.Applying ANSYS software to analysis the deformation of machine structure at different temperatures, the result shows that the overall deformation has the same tendency as the lens group，and can meet temperature requirements. Then making the precision analysis of the optical system and providing a group of measured data. Depended on the measurement results, the error of position for single star ≤7″, the error of angular distance between stars≤10″. The data shows that this design and the product meet the requirement of technique index.

Considering the requirement of high reality and real-time quality dynamic infrared image of an infrared image simulation, a method to design real-time infrared image simulation application on the platform of VC++ is proposed. This is based on visual simulation software Creator and Vega. The functions of Creator are introduced simply, and the main features of Vega developing environment are analyzed. The methods of infrared modeling and background are offered, the designing flow chart of the developing process of IR image real-time generation software and the functions of TMM Tool and MAT Tool and sensor module are explained, at the same time, the real-time of software is designed.

Infrared diagnostic technique is a live detection technique characterized by convenience and fastness. It enables the detection in a live, non-contact, accurate, sensitive and safe manner. Infrared diagnostic technique is an important means of ensuring the safe and reliable operation of the power equipments. The precision infrared imaging of capacitor set by infrared technology can timely detect the equipment faults due to current or voltage-caused heating. It is of high significance for achieving the reactive power adequacy of the system.

This paper designs a compact apochromatic lens with long focal length, which operates over very-broad spectrum from 400nm to 900nm for high resolution image application. The focal length is 290mm, and F-number is 4.5.In order to match CCD sensor, lens resolution must be higher than 100lp/mm. It is a significant challenge to correct secondary spectrum over very-broad spectrum for this application. The paper firstly pays much attention on dispersion characteristic of optical materials over this very-broad spectrum, and dispersion characteristic of glasses is analyzed. After properly glasses combinations and optimal lens structure selected, this compact apochromatic lens is designed. The lens described in this paper comprises fewer lenses, most of them are ordinary optical materials, and only one special flint type TF3 with anomalous dispersion properties is used for secondary spectrum correction. Finally, the paper shows MTF and aberration curve for performance evaluation. It can be seen that MTF of the designed lens nearly reach diffraction limit at Nyquist frequency 100lp/mm, and residual secondary spectrum is greatly reduced to less than 0.03mm (in the lines 550nm and 787.5nm). The overall length of this compact apochromatic lens is just 0.76 times its focal length, and because of fewer lenses and ordinary optical materials widely used, production cost is also greatly reduced.

Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. In this paper, some basic principles and the implementing flow charts of a series of algorithms for target detection are described. These algorithms are traditional two-frame difference method, improved three-frame difference method, background estimate and frame difference fusion method, and building background with neighborhood mean method. On the foundation of above works, an infrared target detection software platform which is developed by OpenCV and MFC is introduced. Three kinds of tracking algorithms are integrated in this software. In order to explain the software clearly, the framework and the function are described in this paper. At last, the experiments are performed for some real-life IR images. The whole algorithm implementing processes and results are analyzed, and those algorithms for detection targets are evaluated from the two aspects of subjective and objective. The results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.

Segmenting greenbelts quickly and accurately in remote sensing images is an economic and effective method for the statistics of green coverage rate (GCR). Towards the problem of over-reliance on priori knowledge of the traditional level set segmentation model based on max-flow/min-cut Graph Cut principle and weighted Total Variation (GCTV), this paper proposes a level set segmentation method of combining regional texture features and priori knowledge of color and applies it to greenbelt segmentation in urban remote sensing images. For the color of greenbelts is not reliable for segmentation, Gabor wavelet transform is used to extract image texture features. Then we integrate the extracted features into the GCTV model which contains only priori knowledge of color, and use both the prior knowledge and the targets’ texture to constrain the evolving of the level set which can solve the problem of over-reliance on priori knowledge. Meanwhile, the convexity of the corresponding energy functional is ensured by using relaxation and threshold method, and primal-dual algorithm with global relabeling is used to accelerate the evolution of the level set. The experiments show that our method can effectively reduce the dependence on priori knowledge of GCTV, and yields more accurate greenbelt segmentation results.

Nowadays as low carbon economy is advocated worldwide, the electricity consumption caused by a huge number of embedded systems is gaining more and more attentions, and power consumption has become a critical issue in embedded system design. After past work of low power consumption technologies in embedded systems is explored, according to the software constituents of embedded systems, this paper divides low power consumption technologies into three levels, in which, the encountered problems, major solutions and applications are clarified. A full vision about low power consumption technologies in embedded systems is described. Finally, this paper discusses some trends of software low power consumption technologies in the future.

In this paper, a mathematical model of TDI CMOS image sensors was established in behavioral level through MATLAB based on the principle of a TDI CMOS image sensor using temporal oversampling rolling shutter in the along-track direction. The geometric perspective and light energy transmission relationships between the scene and the image on the sensor are included in the proposed model. A graphical user interface (GUI) of the model was also established. A high resolution satellitic picture was used to model the virtual scene being photographed. The effectiveness of the proposed model was verified by computer simulations based on the satellitic picture. In order to guide the design of TDI CMOS image sensors, the impacts of some parameters of TDI CMOS image sensors including pixel pitch, pixel photosensitive size, and integration time on the performance of the sensors were researched through the proposed model. The impacts of the above parameters on the sensors were quantified by sensor’s modulation transfer function (MTF) of the along-track direction, which was calculated by slanted-edge method. The simulation results indicated that the TDI CMOS image sensor can get a better performance with smaller pixel photosensitive size and shorter integration time. The proposed model is useful in the process of researching and developing a TDI CMOS image sensor.

In four-transistor (4T) CMOS image sensors (CIS), incomplete charge transfer from the photodiode (PD) to the floating diffusion (FD) node can result in image lag, which is a serious problem affecting the imaging performance. In the paper a low image lag 4T pixel structure for CIS is proposed. Two techniques are adopted to promote complete charge transfer in a 4T pixel. Firstly, the threshold voltage of the reset transistor in the 4T pixel is adjusted to an appropriate negative value to realize a high potential in the FD, which is helpful for the charge (electron) to transfer into FD. Inevitably, a large negative threshold voltage make the source-drain leakage current of the reset transistor can not be ignored. In the design the threshold voltage is chosen to satisfy the requirements of a higher potential in FD and a lower source-drain leakage current of reset transistor simultaneously. Secondly, an additional p-type layer is adopted on the surface of the photodiode, with partially overlapped the channel of the transfer transistor. With an optimized overlap length, neither an apparent potential barrier nor a severe potential pocket can be formed on the route of charge transfer. So a potential distribution under transfer gate conducive to charge transfer is achieved. An identical photomask is used to manufacture the additional p-type layer and the p-type pinned layer of the photodiode, and the latter is formed in selfaligned way, which is economic in process and helpful to control the misalignment of the layer. The simulations are completed in Technology Computer-Aided Design (TCAD) tools. A test chip with 32×10 pixel array has been designed and fabricated in 0.18μm 1P4M CIS process. The experimental results demonstrate that the image lag is below the measurement threshold (using 12-bit ADC) with an additional reset operation adopted. Without the additional reset, the largest measured image lag is 0.18%.

During telescope detection, there is atmosphere overflow and other stray light affecting the system which leads to background disturbance. Thus reduce the detection capability of the system. So it is very necessary to design mechanical structure to suppress the stray light for the telescope detection system. It can both improve the signal-to-noise and contrast of the object. This paper designs the optical and mechanical structure of the 400mm telescope. And then the main baffle, baffle vane, field stop and coating technology are used to eliminate the effect of stray light on the optical and mechanical system. Finally, software is used to analyze and simulate stray light on the whole optical and mechanical system. Using PST as the evaluating standard, separate and integrated analysis of the suppressing effect of main baffle, baffle vane and field aperture is completed. And also get the results of PST before and after eliminating the stray light. Meanwhile, the results of stray light analysis can be used to guide the design of the optical and mechanical structure. The analysis results demonstrate that reasonable optical and mechanical structure and stray light suppression measure can highly reduce the PST and also improve the detection capability of the telescope system, and the designed outside baffle, inside baffle, vanes and coating technique etc. can decrease the PST approximately 1 to 3 level.

In this paper, a robust and fast image registration algorithm suitable for super-resolution is proposed, it yields a solution that precisely registers images with subpixel accuracy. The proposed registration process is carried out in three stages. In first stage, the image edges are extracted and then the corner points which are on the image edges are extracted, where the improved Harris corner algorithm is used in order to reduce the calculation amount. In second stage, for the coarse registration, the NCC (Normalized cross correlation) similarity measure is used to get an initial set of corresponding point pairs, and then a statistical method is employed in order to remove mismatched points. In detail, we calculate the shift (Δx,Δy) of each point pairs, count the frequency of each shift, and then select the shift with most frequency as the image shift, which is expressed as(Δx₀,Δy₀). In third stage, for fine image registration, subpixel image registration is achieved by interpolation. The bicubic interpolation is done in the neighborhood of the inliers (the correspondences with shift (Δx₀,Δy₀) are called as inliers) and the NCC matching and statistical method is used once again to find the correct corresponding point pairs, from which the shifts between the reference and unregistered image are estimated. The experimental results illustrate the registration speed and accuracy of the proposed method improved significantly.

Using the laser absorption spectroscopy and algebraic iterative reconstruction methods, two-dimensional (2D) temperature distribution has been reconstructed with irregular beam distribution. The reconstruction accuracy strongly depends on the beam distribution. Therefore, an optimal design of the beam arrays can reduce the experimental cost and maximize the beam potentiality. This paper introduces the grid weight factor (GridWF) to evaluate the beam distribution relating to the discrete region. The error of the reconstruction is less than 15% using optimal beam distribution, which is lower than the results of non-optimization. As an increase in the number of emitters, the error can be obviously reduced. Two H₂O absorption transitions (7205.25 cm ⁻¹ and 7416.05 cm⁻¹) are adopted in the simulation. The 2D temperature reconstruction with optimal beam distribution and different number of emitters are demonstrated, showing the optimal design of the beam array having excellent reconstructed performance.

In this paper, the research meaning and application of polarization characteristic of laser backscattering of the rough surface has been introduced. By designing experimental optical, using incident light of 632.8nm wavelength red light, the experimental study of light scattering characteristics of the existing roughness blocks and other typical rough target surfaces have been done. Analysis results show that scattered light intensity with the measured roughness of the target, the incident angle has a relationship. If the roughness of the measured target is changed, the corresponding scattering intensity and the degree of polarization will change. And if the materials of the measured targets are not the same, the backscatter intensity trends are not identical. The research of light scattering properties of typical rough targets has a positive significance to further study of the target feature.

This paper describes an effective mosaic algorithm for UAV aerial images under the circumstances that the vehicle is executing a multiple-strips flying task. The proposed algorithm relies on two parts. One part is the basic image mosaic method which has three steps: firstly, an PCA-GSIFT is constructed to get the key points of the two images to be stitched, secondly, to get the matched pairs, an innovated matched pairs filter is presented, thirdly, to complete the registration and fusion, a weighted average method is implemented. And the other part of the new algorithm is the multiple-strips images mosaic strategy based on a global modulation strategy. Experimental results show that the approach has strong stabilization as well as high efficiency and performs excellent in multiple-stips flying UAV’s panorama generating .

In order to obtain sharp remote sensing images, the image stabilization technology of space camera and the remote sensing image restoration technology are usually used now. Vibration detection is the key to realize these technologies: an image stabilization system needs the displacement vector derived from vibration detection to drive the compensation mechanism; and the remote sensing image restoration technology needs the vibration displacement vector to construct the point spread function (PSF). Vibration detection not only can be used to improve image quality of panchromatic camera, infrared cameras and other optical camera, also is motion compensation basis of satellite radar equipment. In this paper we have constructed a vibration measuring method based on Fiber optic gyro (FOG). FOG is a device sensitive to angular velocity or angular displacement. High-precision FOG can be used to measure the jitter angle of the optic axis of a space camera fixed on satellite platform. According to the measured data, the vibration displacement vector of the imaging plane can be calculated. Consequently the vibration data provide a basis for image stabilization of space camera and restoration of remote sensing images. We simulated the vibration of a space camera by using a piezoelectric ceramic deflection platform, and calibrated vibration measurement by using laser beam and a high-speed linear array camera. We compared the feedback output of the deflection platform, the FOG measured data and the calibrated data of the linear array camera, and obtained a calibration accuracy better than 1.5 μrad.

The traditional Hausdorff measure, which uses Euclidean distance metric (L2 norm) to define the distance between coordinates of any two points, has poor performance in the presence of the rotation and scale change although it is robust to the noise and occlusion. To address the problem, we define a novel similarity function including two parts in this paper. The first part is Hausdorff distance between shapes which is calculated by exploiting shape context that is rotation and scale invariant as the distance metric. The second part is the cost of matching between centroids. Unlike the traditional method, we use the centroid as reference point to obtain its shape context that embodies global information of the shape. Experiment results demonstrate that the function value between shapes is rotation and scale invariant and the matching accuracy of our algorithm is higher than that of previously proposed algorithm on the MEPG-7 database.

According to the characteristics of infrared and visible images, a new image fusion method based on region growing and contourlet transform is proposed in this paper. To obtain more complementary information, the method is designed as a two-stage procedure. Firstly, the input infrared image is processed with region growing to segment the thermal target. Different fusion rules are adopted in target and background regions, respectively. For the target region, local energy is utilized as the fusion rule of the first fusion to fuse the thermal target and the visible image, while for the non-target region, we reserve the visible background information. Secondly, in order to fully add original information of the source images and avoid loss of information caused by segmentation, we make the second fusion between the visible image and the result image of the one-stage fusion. For good properties of localization, directionality and anisotropy, we adopt contourlet transform as the second fusion method. Experiments are carried out and the results show that our method is clearer in visual quality and effective in quantitative evaluations and the fused images are better than those resulting of using wavelet transform and contourlet transform.

The dual-band image fusion algorithm is presented based on infrared radiation characteristics. It is a more accuracy solution, in terms of the spectral, than the wavelet-based image fusion. The fusion algorithm and quality assessment is then applied to demonstrate its performance. Firstly, the gray value of thermal image is converted into corresponding radiation extiance. Secondly, the relationship between the radiation exitance and temperature in 8μm~12μm is fitted by applications of least square method. Combined with Planck blackbody radiation theory, the temperature value of different Pixel of the thermal image is obtained by calculating the radiation. Then the radiation of LWIR image scene in MWIR spectral range is derived through Planck's Formula. Thirdly, the deduced radiation, which reflects the details of the LWIR scene, is quantified and introduced into the MWIR image. Finally, the simulation of dual-band image fusion is obtained by Matlab. The results show that the objectives of image fusion not only retain the abundant spectral information of the original images, but also gain additional information by processing the dual-band data. Thus the dual-band image fusion can increase detection, recognition and identification ranges compared with the original MWIR and LWIR data.

Recently excellent infrared detectors have been demonstrated using InAs/GaSb superlattice materials sensitive at wavelength from 3um to greater than 32um. Using empirical tight binding method (ETBM), different structures as InAs(xML)/GaSb(8ML), (x=2, 4, 6, 8) and InAs(14ML)/GaSb(7ML) were designed for various cut-off wavelengths from short to long IR wavelength. These materials were grown by MBE with valved cracker cells for arsenic and antimony on p-type GaSb(001) substrates. The microstructure and the bandgap Eg were verified by high resolution X-ray diffraction and photoresponse spectra. The temperature dependence of Eg and photoresponse responsivity Rv were studied. The differential resistance under zero bias R₀ in MWIR photodiode was measured up to 10⁶ ohms. The ideality factor in the range of 1.5 to 2.1 indicates the generation-recombination current and surface leakage current are the dominant leakage in the depletion region. These results will promote InAs/GaSb superlattices infrared detectors research in multi-color from short to long wave IR application.

In order to effectively simulate infrared features of the scene and infrared high light phenomenon, Based on the visual light illumination model, according to the optical property of all material types in the scene, the infrared imaging illumination models are proposed to fulfill different materials: to the smooth material with specular characteristic, adopting the infrared imaging illumination model based on Blinn-Phone reflection model and introducing the self emission; to the ordinary material which is similar to black body without highlight feature, ignoring the computation of its high light reflection feature, calculating simply the material’s self emission and its reflection to the surrounding as its infrared imaging illumination model, the radiation energy under zero range of visibility can be obtained according to the above two models. The OpenGl rendering technology is used to construct infrared scene simulation system which can also simulate infrared electro-optical imaging system, then gets the synthetic infrared images from any angle of view of the 3D scenes. To validate the infrared imaging illumination model, two typical 3D scenes are made, and their infrared images are calculated to compare and contrast with the real collected infrared images obtained by a long wave infrared band imaging camera. There are two major points in the paper according to the experiment results: firstly, the infrared imaging illumination models are capable of producing infrared images which are very similar to those received by thermal infrared camera; secondly, the infrared imaging illumination models can simulate the infrared specular feature of relative materials and common infrared features of general materials, which shows the validation of the infrared imaging illumination models. Quantitative analysis shows that the simulation images are similar to the collected images in the aspects of main features, but their histogram distribution does not match very well, the reasons are analyzed and the further improvement direction is proposed. Theories and experiments show that the validation of the infrared illumination models in the paper.

The jamming effectiveness evaluation of infrared imaging system is an important part of electro-optical countermeasure. The infrared imaging devices in the military are widely used in the searching, tracking and guidance and so many other fields. At the same time, with the continuous development of laser technology, research of laser interference and damage effect developed continuously, laser has been used to disturbing the infrared imaging device. Therefore, the effect evaluation of the infrared imaging system by laser has become a meaningful problem to be solved. The information that the infrared imaging system ultimately present to the user is an image, so the evaluation on jamming effect can be made from the point of assessment of image quality. The image contains two aspects of the information, the light amplitude and light phase, so the image correlation can accurately perform the difference between the original image and disturbed image. In the paper, the evaluation method of digital image correlation, the assessment method of image quality based on Fourier transform, the estimate method of image quality based on error statistic and the evaluation method of based on peak signal noise ratio are analysed. In addition, the advantages and disadvantages of these methods are analysed. Moreover, the infrared disturbing images of the experiment result, in which the thermal infrared imager was interfered by laser, were analysed by using these methods. The results show that the methods can better reflect the jamming effects of the infrared imaging system by laser. Furthermore, there is good consistence between evaluation results by using the methods and the results of subjective visual evaluation. And it also provides well repeatability and convenient quantitative analysis. The feasibility of the methods to evaluate the jamming effect was proved. It has some extent reference value for the studying and developing on electro-optical countermeasures equipments and effectiveness evaluation.

The calculation and theoretical analysis of water spray infrared attenuation have been partially solved, where multi-scattering, distribution of droplet diameter, droplet density and water optical character in the infrared atmosphere window, etc. are considered. However, under the premise that droplet density does not change, is there a stair phenomenon in water spray monochromatic infrared transmission? If yes, what are the reasons? These questions are still to be answered. In the calculation, with the unchanged general droplet density, through changing the droplet size of water spray, the corresponding water spray spectrum 3~12μm infrared transmission is calculated with MIE scatter theory and Single Diameter Monte Carlo Method. The results show that there are two conditions for the occurrence of infrared transmission stair phenomenon of water spray: 1) with the increase of droplet diameter, the droplet extinction index decreasing speed is consistent with the square speed of droplet diameter increase; 2) the corresponding infrared albedo change small. Meanwhile, results also show that when the infrared wave length is less than 3.3μm or more than 5.7μm, there is no stair-like phenomenon in water spray transmission curve. While between 3.3 and 5.7μm, the spectrum infrared transmission stair phenomenon will occur in certain droplet diameter range.

As infrared zoom systems change the focal length continuously, remain images stability and keep good image quality during the process of zoom, it is widely applied to infrared navigation, infrared detection, infrared-guided etc vehicular and airborne area. In order to satisfy the growing demand of infrared continuous zoom system, a zoom ratio of ten times long-wave infrared continuous zoom optical system that based on an uncooled detector was designed. System guided by the zoom theory of positive groups of compensation, calculated the initial structure of the system and according to the system of optical parameters with using ZEMAX software for optical design did an aberration balance and optimized, then the optical system image quality was systematically analyzed and evaluated. The result showed that the modulation transfer function (MTF) was above 0.4 within the whole focal range at spatial frequency 16 lp/mm, the root mean square radius of maximum dispersion spot was smaller than a pixel dimension and it met the requirements of the system imaging quality when F/# was 2, continuous zoom range was from 40 mm to 400 mm and the image size was 12 mm. The design of the system realized the requirements of compact structure, large zoom ratio, easily assembled and excellent image quality to optical system for infrared imaging.

This paper presents a method for multi-exposure images fusion based on wavelet packet transform, combining the local energy distributions of multi-exposure images with the edge detection. After decomposing two images involved in fusion into sub images in low-frequency and high-frequency with wavelet packet transform, we use different methods for low-frequency and high-frequency to obtain fusion coefficients. In low frequency processing, the method that threshold value is set for local energy is used while the edge detection method is used in high frequency, where the edge detection operator help compute the information quantity of different high frequency images. Then the coefficients for fusion are selected according to different strategies adopted for low- and high-frequency. Finally, the fusion image is reconstructed through inverse wavelet packet transform. The result shows that the fusion method is effective and the fusion image can preserve the details of the each input image successfully.

Image fusion takes a significant part in the technology of information enhancement. By analyzing the advantages and disadvantages of previous methods , this paper proposes an improved wavelet-transform-algorithm, which both considers the fusion methods of low-frequency and high-frequency components: On the low-frequency sub-band aspect, introducing a border detector operator in order to collect the border information of images that can be the basis of selective fusion method; On the high-frequency sub-band aspect, applying the local-standard-deviation to being the basis of selective and weighted-averaging fusion method. The experiments reveal that the proposed algorithm contributes to enhancing the definition and contract ratio of the fused images, thereby it’s a valid method.

Geosynchronous satellite has obvious limitations for the weight and the scale of payloads, and large aperture optical system is not permitted. The optical diffraction limit of small aperture optical system has an adverse impact on the resolution of the acquired images. Therefore, how to get high resolution images using super-resolution technique with the acquired low resolution images becomes a popular problem investigated by researchers. Here, we present a novel scheme to acquire low resolution images and process them to achieve a high resolution image. Firstly, to acquire low resolution images, we adopt a special arrangement pattern of four CCD staggered arrays on the focal plane in the remote sensing satellite framework .These four CCD linear arrays are parallelized with a 0.25√2 pixel shift along the CCD direction and a 1.25 pixel shift along the scanning direction. The rotation angle between the two directions is 45 degree. The tilting sampling mode and the special arrangement pattern allow the sensor to acquire images with a smaller sampling interval which can give the resolution a greater enhancement. Secondly, to reconstruct a high resolution image of pretty good quality with a magnification factor 4, we propose a novel algorithm based on the iterative-interpolation super resolution algorithm (IISR) and the new edge-directed interpolation algorithm (NEDI). The new algorithm makes a critical improvement to NEDI and introduces it into the multi-frame interpolation in IISR. The algorithm can preserve the edges well and requires a relatively small number of low-resolution images to achieve better reconstruction accuracy .In the last part of the paper, we carry out a simulation experiment, and use MSE as the quality measure. The results demonstrate that our new scheme substantially improves the image resolution with both better quantitative quality and visual quality compared with some previous normal methods.

In the process of medical imaging (MI) reconstruction, filtering of original projection data is a key step to overcome artifact of the reconstructed image. Although some classical filters can be used into FBP algorithm, some drawbacks limit its application in practice, especially for the data polluted by non-stationary random noises. To overcome the shortcomings of these traditional filtering, an improved FBP combined with a shift-invariant wavelet threshold denoising algorithm is proposed in this paper. In the experiments, the reconstructed effects were compared between the improved algorithm, classical soft and hard threshold denoising methods. Experimental results illustrated that the reconstruction effect of improved FBP algorithm is better than that of others. In addition, two evaluation standards, i.e. mean-square error (MSE), peak-to-peak signal-noise ratio (PSNR) were used to compare the results of different algorithms. It was found that the reconstructed effects of the improved FBP combined with shift-invariant wavelet hard threshold function based on RL filter is better than others. Therefore, this improved FBP algorithm has potential value in the medical imaging.

Nowadays, infrared imaging systems play important roles in the field of civil and military. Especially small infrared target detecting and recognizing is one of the most widely use. The capability of target-detection algorithm is an important index of the system. This paper presents a novel algorithm for detecting a small moving target in infrared (IR) image sequences and finding its mass center, and recording the target moving track. In the target searching and recognizing algorithm of infrared image sequences, infrared image sequence is broken into frames, filtered by spatial filter algorithm, which helped to reduce granular noise. We use the Canny algorithm factor to find the edge of the target, and the result of detecting target edge is process by ecological open-loop filter method, including erosion and dilation algorithm with a same scale. Then, the candidate targets are recognized and saved temporarily. In order to get the mass centers of the candidate targets, the valid area of the candidate targets is defined by different weight valves, and then the mass centers are calculated by weighted average algorithm, and record per frame. After got several frames mass centers of the candidate targets, we get rid of the non-target mass centers by frame difference algorithm, and get the real mass center of the small moving infrared target. If the background is observed for enough time, the effect of frame difference algorithm is more efficiency. Finally, the moving track of the target is found out. The infrared (IR) image sequences used here are obtained through an IR camera in the laboratory, which uses a 288*384 silicon infrared image sensor produced by ULIS company. The methods referred above are realized and simulated on compute with Matlab. Theory analysis and experiments prove the method is reasonable and efficient.

How to remove the noise in infrared image effectively with detail preserving is a significant but difficult problem in infrared image processing. Various methods have been proposed to obtain good results. However, these algorithms usually cannot distinguish noise and detail efficiently, which leads to smoothing some details in infrared images. Recently a novel local measure called relative total variation (RTV) is proposed to accomplish effective texture removal. RTV measure is combined with a general windowed total variation measure and a novel inherent variation measure to smooth the image texture effectively while preserving the main structure. In this paper, using detail preserving smoothing method via RTV, a multi scale denoising algorithm for infrared image is proposed. Firstly, the infrared image is decomposed into several scales by non-subsampled Contourlet transform (NSCT). NSCT decomposition does not do any down sampling or up sampling, thus the results are not band limited. Secondly，the algorithm applies RTV based detail preserving denoising method for each decomposed layers. Different smoothing parameters are respectively used to adjust the denoising levels in different scales. Finally, various synthetic weights are utilized to different layers to reconstruct the final infrared denosing results. Compared with other infrared denoising approaches, the quantitative comparisons demonstrate that the proposed method could well suppress the noise of infrared image while preserving the edge details effectively. Both visual quality and objective measure results show that this method is efficient and has a good application in infrared image denoising.

Modern infrared focal plane arrays (IR FPA) with high dynamic range, and multiband versions are being deployed in fielded systems. It needs to develop advanced scene projection technology to operate both in laboratory testing for hardware-in-the-loop simulation and validation of fielded units immediately prior to mission use. One of the fiber array visible to infrared imaging transducer is introduced. Different from the fiber bundle, the fiber array is etched on the substrate material. The property of transducer is determined by the substrate material. Polyimide (PI) film has the property of high dynamic range for temperature resistant, electric insulating, radiation resistant, good thermosetting and thermomechanical effect. The heat diffusion property of PI film is analyzed by experimental study. For experimental study, samples of with sputtered graphite on surface and different thickness of PI film were made. Using the visible light irradiate on the film and a high speed infrared camera capture the temperature information. The time of raising temperature process and the max temperature were recorded. The different energy of visible light was tried for the max temperature for samples. The result show the PI film can be achieved to 600K and has high thermal efficiency. And the surface film with good absorptivity is also important for heat transforming. PI film can be used as one of the material in the Infrared imaging transducer for high dynamic range and multiband radiation.

In high speed flight, the aero-optical effect greatly affects infrared imaging system. An experiment investigating heating window radiance was conducted based the fluid computational simulation results. The paper gave the facilities needed and the procedures for experiment performance. The experiment data was analyzed by means of target signature evaluation principle, target contrast, SNR, gray level correlation index and gradient correlation index was computed from 4-bars infrared image. The results showed that the image region of interest was greatly affected by the heating window radiation. And some pre-processing skills should be introduced before implementing the target recognition and tracking algorithms. It is meaningful for validating performance of infrared imaging system with non-cooling window and to development methods of suppressing the hot dome radiation to reduce the image degradation.

In modern image processing, due to the development of digital image processing, the focus of the sensor can be automatically set by the digital processing system through computation. In the other hand, the auto-focusing synchronously and consistently is one of the most important factors for image mosaic and fusion processing, especially for the system with multi-sensor which are put on one line in order to gain the wide angle video information. Different images sampled by the sensors with different focal length values will always increase the complexity of the affine matrix of the image mosaic and fusion in next, which potentially reducing the efficiency of the system and consuming more power. Here, a new fast evaluation method based on the gray value variance of the image pixel is proposed to find the common focal length value for all sensors to achieve the better image sharpness. For the multi-frame pictures that are sampled from different sensors that have been adjusted and been regarded as time synchronization, the gray value variances of the adjacent pixels are determined to generate one curve. This curve is the focus measure function which describes the relationship between the image sharpness and the focal length value of the sensor. On the basis of all focus measure functions of all sensors in the image processing system, this paper uses least square method to carry out the data fitting to imitate the disperse curves and give one objective function for the multi-sensor system, and then find the optimal solution corresponding to the extreme value of the image sharpness according to the evaluation of the objective function. This optimal focal length value is the common parameter for all sensors in this system. By setting the common focal length value, in the premise of ensuring the image sharpness, the computing of the affine matrix which is the core processing of the image mosaic and fusion which stitching all those pictures into one wide angle image will be greatly simplified and the efficiency of the image processing system is significantly improved.

We propose an improved Lucas-Kanade template tracking method with drift correction, which can be applied in rigid extended object. Due to error accumulation, primary template tracking method leads to template drift and loses object gradually. In order to alleviate template drift, SIFT (Scale Invariant Feature Transform) feature is used to correct the template drift. SIFT feature is invariant to scale, rotation even affine transformation, so, according to matching SIFT key-points between frames, the affine parameters of object transformation can be computed, then the current template position can be obtained by affine parameters and primary template position. The experiment results prove that the improved template tracking method based on SIFT drift correction can more accurately track the rigid extended object and can alleviate the tracking position drifting effectively.

During the course of reflecting light-wave, the surface of snow will cause polarimetric properties which are related to the nature of itself. Thus, detection of the polarimetric information for snow has become a new remote sensing monitoring method. In this paper, starting from the perspective of multi-angle polarimetric reflectance, the multi-angle spectral-polarimetric instrument was used to obtain the multi-angle visible and near infrared spectral-polarimetric characteristic data of snow in different melting states. And then, the change rule between polarimetric properties with different affecting factors, such as viewing zenith angle, incidence zenith angle of the light source, relative azimuth angle, waveband of the detector as well as different types of snowmelt were discussed. The visible and near infrared spectral-polarimetric properties of snow has not only important theoretical significance for the quantitative analysis of snowmelt properties, but also wide application prospect, and provides new ideas and methods for the quantitative research on snow using the remote sensing technology.

In recent years many optical reconnaissance systems have characteristic called “cat-eye effect”, it means that the incident light in such system can be reflected back along the same path of incidence. And these optical systems can also be called “cat-eye target”. The scanning-style target’s reflective surface appears in the focal plane at a certain period—Only when the reflective surface is in the focal plane that the target can reflect the incident light. Therefore, when active laser detection systems launch laser impulse to detect these targets, the detection result is uncertain. Current research has little analysis for uncertain detection result of scanning-style target. In order to describe such uncertain detection result, in this paper, we first analyzed the time factors and put forward detection probability formulas; Second, we use MATLAB to simulate the detection result of scanning-style cat-eye target, and we received the quantitative relationship curve between the frequency and the value of detection probability; Furthermore, we found that the value of detection probability is related to the detection time and the frequency of laser impulse. The result of the simulated experiment indicated that we could modulate the frequency of laser impulse launched by active laser system to increase the value of detection probability, it will help improve the detection quality of the active laser detection systems.

Due to the extra wide field of view, fisheye optical systems are appropriately applied in space camera for scouting large-scale objects with near-distance. At the same time, because of the violent sunlight linger within the field of view more than other optical system and more stray light occur during the period, to design proper lens-hood can effectively reduce the sunshine time. Another distinct characteristic of fisheye optical system is the first protrude lens, which is contrived with negative focus to trace the ray with angle about even above 90 degree of incidence. Consequently, the first lens is in danger of damaging by scratching when operating the camera during the ground experiments without lens-hood. Whereas on account of the huge distortion which is the third mainly characteristic of fisheye optical system, to design appropriate lens-hood is a tough work comparing with other low-distortion optical system, especially for those whose half diagonal field is more than 90°. In this paper, an research carried out on the design lens-hood for fisheye is proposed. In the way of reverse ray-tracing, the location on the first lens and point-vector for each incident ray can be accurately calculated. Thus the incident ray intersecting the first lens corresponds to the boundary of the image sensor form the effective object space. According to the figure of the lens and the incident rays, the lens-hood can be confirmed. In the proposed method, a space fisheye lens is presented as a typical lens, whose horizontal field and vertical field are 134°, diagonal field is up to 192°, respectively. The results of design for the lens-hood show that the lingering time of sunshine is shorten because of obstructing some redundant sunlight, and the first outstanding lens are protected in the most degree.

This paper presents a real-time processing system designed for infrared FPA. The real-time processing is a key technology in the infrared image processing system^[1]. In this paper, the pre-processing and segmentation approaches are combined in order to achieve a good result from infrared images which have large noise, complex background and ambiguous target^[2]. This design is a real-time IR image processing system based on Xilinx's VIRTEX-5, fully using of VIRTEX-5 FPGA’s high performing, the FPGA embedded Xilinx's MicroBlaze processor core, and high-performance pre-processing function modules. Data signals processed by FPA can be collected to carry out filtering calculation, and the LCD displays the image, user can control the system by touching screen real-time.

In order to evaluate and test the image quality of large aperture telescope, the most directly method is adopting the collimator and test the telescope system with full aperture. Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP) commenced developing the large aperture collimator for interferometric and image quality testing of meter scale optical systems under cryogenic, vacuum conditions. The aperture of the collimator which has been on the conceptual design phase is 1.5m diameter, and the optical configuration is Cassegrain, the focus is 50m. The material of reaction bonded Silicon Carbide (RB-SiC) produced by CIOMP will be used as the primary mirror substrate. And the figure accuracy of the primary mirror will be polished better than 15nm (RMS). The collimator will be working in a vacuum chamber and face down vertically to the unit under test. The application requirements, specification requirements, and some key technology are demonstrated and analysed with finite element analysis (FEA) in the paper. The feasibility, error budget, and hazards evaluation of the collimator are fulfilled by the FEA results. It demonstrated that the conceptual design meet the requirements of the 1.5m aperture vertical collimator, and could achieve the high accuracy requirements of the wavefront for the beam of light in the vacuum chamber, which the wavefront error should less than 32nm(RMS). Mechanical alignment errors induced by thermal and structural perturbations are monitored with an auto-focusing system to enable focus compensation. The ambient temperature of the collimator in chamber are controlled allowing testing while the chamber shrouds and test unit are brought to cryogenic temperatures. With the high accuracy of the wavefront, the collimator could test the image resolution, modulation transfer functions (MTFs), point spread functions (PSFs), encircled energy, wavefront error, best focus, etc. for optical systems. And the conceptual design could be consulted to other large aperture collimators.

Some thermal imaging experiments have been done about a building with a door made of iron, copperplate and aluminum flake, several trees, marbles, a glass window and a concrete wall under different conditions in a winter day while the environmental temperature and relative humidity are simultaneously measured by an electronic sensor. The experimental results show that the thermal imaging temperatures of the targets are related to the category of materials, and presenting some laws with the environment temperature changing. All of the thermal imaging temperature of the targets obviously varies with the atmospheric environment temperature by the large temperature difference. The changes of the surface temperature of metals are more obviously than nonmetals. The thermal imaging temperature of the door made of iron is more easily affected by the atmospheric environment temperature than copperplate while aluminum flake is more difficultly affected than copperplate under the same condition. The temperature of an ordinary concrete wall is obviously higher than the one painted by oil paint. Under the same condition, the changes of glasses are the most in all of the nonmetal targets.

In an infrared optical system, the thermal radiation of high temperature components is the major noise as stray radiation that degrades the system performance. Backward Monte Carlo method based on radiation distribution factor is proposed to perform the stray radiation calculation. Theoretical deduction and some techniques are presented, considering the semitransparent element like IR window as radiation emitter. The radiation distribution factors are calculated with ray tracing from the detector to radiation sources. Propagation of stray radiation and its distribution on the detector are obtained simultaneously. It is unnecessary to implement ray tracing again to study the effect of different temperatures for a given system, expect that the geometry or radiative property is changed. An infrared system is simulated using this method. Two different situations are discussed and the analysis shows that stray radiation is mainly created by IR window and lens tube.

The format of infrared focal plane arrays (IRFPAs) is continuously increasing, and the spatial non-uniformity in the irradiance affects the result of large-format IRFPAs’ responsivity measurement. When placed in the test system, different pixels on the IRFPA receive different radiation flux due to the specific geometric setup of the dewar, resulting signal response uniformity. This is not the inherent characteristics of the IRFPA and thus should be corrected. The existing methods of correcting irradiance spatial non-uniformity simply consider the solid angle subtended by the aperture of the cold shield viewing from the center of a pixel. However, these methods are only applicable for the case of an infinite blackbody behind the cold shield. This paper presents a more comprehensive and appropriate correction, taking account of the specific geometric setup of the dewar, especially a dewar window of finite size. The relative irradiance received by different pixels on an IRFPA, as a correction factor, is simulated directly through matrix calculations. We apply the FOV correction profile to a 640 x 512 HgCdTe IRFPA with a pitch of 25μm, finding that responsivity ratio of the peripheral pixels to the central pixels on the IRFPA has changed from an original value of 88.0% to 96.4% after correction. This method has been proven to be useful and effective in obtaining more accurate description of the IRFPA performance for further analysis.

The fusion of infrared and visible light images can effectively improve the ability of detail description and hot taget representation. For this purpose, a novel image fusion algorithm based on nonsubsampled shearlet transform (NSST) was presented in this paper. Firstly, the NSST was adopted to decompose the two source images at different scales and directions, and the low-frequency and high-frequency sub-band coefficients of the images were obtained. Secondly, we used a modified fusion rules. For the low-frequency coefficients of the fused image, we summed up the low-frequency coefficients of two source images, and then subtracted the average of the mean values of the two low-frequency coefficients. Meanwhile, considering that adjacent pixels had strong correlation, an improved selection principle based on the local energy matching was developed for the high-frequency coefficients of the fused image, which was also consistent with the characteristics of the human vision system. Finally, the fused image was reconstructed by performing the inverse NSST on the combined coefficients. Experimental results demonstrate that the proposed algorithm can effectively integrate important information from infrared and visible light images. And comparing with some other image fusion algorithms, the proposed algorithm can further enhance the contrast of fused images and protect more detail information of source images. Both visual quality and objective evaluation criteria show that the method has a higher performance.

The GCPs are widely used in remote sense image registration and geometric correction. Normally, the DRG and DOM are the major data source from which GCPs are extracted. But the high accuracy products of DRG and DOM are usually costly to obtain. Some of the production are free, yet without any guarantee. In order to balance the cost and the accuracy, the paper proposes a method of extracting the GCPs from SRTM data. The method consist of artificial assistance, binarization, data resample and reshape. With artificial assistance to find out which part of SRTM data could be used as GCPs, such as the islands or sharp coast line. By utilizing binarization algorithm , the shape information of the region is obtained while other information is excluded. Then the binary data is resampled to a suitable resolution required by specific application. At last, the data would be reshaped according to satellite imaging type to obtain the GCPs which could be used. There are three advantages of the method proposed in the paper. Firstly, the method is easy for implementation. Unlike the DRG data or DOM data that charges a lot, the SRTM data is totally free to access without any constricts. Secondly, the SRTM has a high accuracy about 90m that is promised by its producer, so the GCPs got from it can also obtain a high quality. Finally, given the SRTM data covers nearly all the land surface of earth between latitude -60° and latitude +60°, the GCPs which are produced by the method can cover most important regions of the world. The method which obtain GCPs from SRTM data can be used in meteorological satellite image or some situation alike, which have a relative low requirement about the accuracy. Through plenty of simulation test, the method is proved convenient and effective.

Due to the low contrast ,lack of details and difficulties to distinguish target from background in traditional infrared(IR) imaging systems, the detection and recognition probability of camouflage infrared target is relatively low. Compared with the traditional IR imaging systems, the method of polarimetric imaging uses polarization information, which can help detect and isolate manmade objects from the natural environment in complex. The method of infrared polarimetric imaging is proposed in this paper. The experiment builds the IR polarimetric imaging system. An IR polarizer made of BaF2 is assembled before the IR camera. By rotating the IR polarizer, twelve polarization images are obtained at every thirty degree. The gray levels of the images are calculated by program. Stokes polarization vector representation is introduced to calculate I of stokes vector and degree of linear polarization (DoLP) with polarization images. According to the character of parameter I of stokes vector and DoLP, we propose an IR polarization fusion method based on Shearlets using regional saliency analysis. This method can highlight the target area and have good performance in the fusion of IR radiation information and IR polarization characteristics. To test the effectiveness of this method, we use mid-wave infrared (MWIR) camera and long-wave infrared(LWIR) camera to get real images. Compared with original image, both the subjective and objective evaluation results indicate that the enhanced images obtained by our method have much more image details and polarization information, which is useful for target detection and recognition.

A new face recognition system was proposed, which used active near infrared imaging system (ANIRIS) as face images acquisition equipment, used kernel discriminative common vector (KDCV) as the feature extraction algorithm and used neural network as the recognition method. The ANIRIS was established by 40 NIR LEDs which used as active light source and a HWB800-IR-80 near infrared filter which used together with CCD camera to serve as the imaging detector. Its function of reducing the influence of varying illuminations to recognition rate was discussed. The KDCV feature extraction and neural network recognition parts were realized by Matlab programming. The experiments on HITSZ Lab2 face database and self-built face database show that the average recognition rate reached more than 95%, proving the effectiveness of proposed system.

In recent years, with the development of space technology, the infrared earth simulator that can only provide an earth angle could not meet the requirements of the calibration tests for earth sensor on the ground, then the research on infrared earth simulator which can provide a variety of earth angles has become an inevitable trend. Based on the collimated infrared earth simulator’s working principle and design requirements, aimed at these three orbit height 18000Km, 35786 Km and 42000 Km, a high altitude orbits collimating infrared earth simulator is developed by adopting the collimation and the earth diaphragm alterable project. Applied ZEMAX software to design a meniscus of germanium collimating lens, the simulation results show that the lens has a effective aperture of 240mm, provide the optimum position and diameter of the earth diaphragms correspond following three earth angles of 30.42°, 17.46° and 15.19°. Used ANSYS software to do finite element analysis for the key components of the mechanical structure. Finally, validate the deviation accuracy of flare angles and beam parallelism via theoretical analysis and practical calculation. The results indicate that the errors of three flare angles of the earth are all less than ±0.05, can meet the accuracy requirements of infrared earth simulator for infrared earth sensor’s calibration testing on the ground. Key words: Infrared earth sensor, Earth simulator, Variable angular, Germanium collimating lens

An improved CMOS readout integrated circuit (ROIC) for N-on-P very long wavelength (VLWIR) detectors is designed, which has the ability to operate with a simple background suppression. It increases the integration time and the signal-to-noise ratio (SNR) of image data. A buffered gate modulation input (BGMI) cell as input circuit provides a low input resistance, high injection efficiency, and precise biasing voltage to the photodiode. By theoretically analyzing the characteristic parameters of MOS device at low temperature, a high gain’s feedback amplifier is devised which using a differential stage to provide the inverting gain to improve linearity and to provide tight control of the detector bias. The final chip is fabricated with HHNEC 0.35um 1P4M process technology. The measurement results of the fabricated readout chip under 50K have successfully verified both readout function and performance improvement. With the 5.0V power supply, ROIC provides the output dynamic range over 2.5V. At the same time, the total power dissipation is less than 200mW, and the maximum readout speed is more than 2.5MHz.

A rapid method to generate infrared images based on image synthesis is proposed in this paper. At first, a three-dimension geometric model of the airplane is created by 3DMax software. Infrared radiance model of the airplane in accordance with infrared radiation theory is established, and the impact of atmospheric attenuation is considered, then the infrared images of airplane are generated. Finally, the synthesis of the generated images and actual shooting background images is achieved. To improve simulation reliability and fidelity, several aspects are thought in this paper for the synthesis, they are the atmospheric effect, the optical of imaging system effect, the random noise of detector, the synthesis revision of generated image and actual shooting background image. Experiment show that the simulation credibility is improved obviously, and the synthesis speed is advanced to 100 frames per second. The running environment is: PC, 512MB of RAM, 1.60GHz of CPU frequency. This method will be reference for testing and evaluating infrared search and track system.

Ground target detection is very important in precise infrared imaging guidance. To address this problem, an accurate tracking algorithm of the key points, i.e., vertex of buildings is proposed. First, the feature points are extracted by Kanade-Lucas-Tomasi (KLT) algorithm, and the template of feature points is updated constantly in the tracking process according to the offset. Then based on the extracted feature points, the key point can be positioned using the geometric relation between the feature points and the key point. Third, the algorithm tracks the feature points and uses the geometric relation to track the key point in the next frame. The experimental results demonstrate the effectiveness of the proposed algorithm in tracking the key point of buildings in front-lower infrared image sequences for long time precise guidance.

FPGA(Field-programmable gate array) is programmable device, characterized by high speed and reconfiguration. We could test the circuit programmed by HDL (Hardware Description Language). By observing results of simulations through ModelSim, developers could fix logic errors. Also, they could analyze performance of circuits by the results. In the system, we build the Gigabit Ethernet development platform based on a FPGA. This paper presents the technique of FPGA and Gigabit Ethernet, as well as relevant techniques. On the basis of merits and drawbacks of different design proposals and real demands, we take the EP3C10E144C8N chip belonging to the series of Cyclone III produced by Altera corp. as main controller chip. By the use of an AX88180 MAC chip produced by ASIX Electronics Corporation and a RTL8211E physical chip by Realtek Semiconductor Corporation, we build the development platform. At the receiving end, we capture data frames from the network adapter by winpcap programming and throw video data in the buffer. Considering large amounts of data in the real-time transportation, we design fixed-length queue as the primary structures for buffer. Size of a buffer unit is 32KB, which means that 32 packets can fill the buffer. When the buffer is full, we put the buffer unit to the end of the queue. We get data from buffer and hand it over to application process to display and store video data. When packet loss is detected by the system, log file will record it and thus we can check how many packets lose. The simulations by Quartus II and practical application proves that the system is stable, featuring high speed and low cost. It can be used in various high speed real-time transmission with little modification.

A point target detection algorithm for IR image is proposed based on spatial statistics. Firstly, according to the spatial correlation of atmosphere background in infrared image, the spatial statistical analysis method is adopted, and a background suppression algorithm based on Kriging is put forward. Secondly, using peak detection algorithm merged with Kriging, the problem of high false-alarm probability for adaptive threshold filter is solved by dual channel filter. The result shows that the detection probability of the algorithm reaches to 99 percent when the input SCR is no less than 6 and probability of false alarm is between 1×10^-3 and 1×10^-4.

The imaging through atmospheric turbulence is an inevitable problem encountered by infrared imaging sensors working in the turbulence atmospheric environment. Before light-rays enter the window of the imaging sensors, the atmospheric turbulence will randomly interfere with the transmission of the light waves came from the objects, causing the distribution of image intensity values on the focal plane to diffuse, the peak value to decrease, the image to get blurred, and the pixels to deviate, and making image identification very difficult. Owing to the fact of the long processing time and that the atmospheric turbulent flow field is unknown and hard to be described by mathematical models, dynamic simulation for distortion Image with turbulence atmospheric transmission effects is much more difficult and challenging in the world. This paper discusses the dynamic simulation for distortion Image of turbulence atmospheric transmission effect. First of all, with the data and the optical transmission model of the turbulence atmospheric, the ray-tracing method is applied to obtain the propagation path of optical ray which propagates through the high-speed turbulent flow field, and then to calculate the OPD from the reference wave to the reconverted wave front and obtain the point spread function (PSF). Secondly, infrared characteristics models of typical scene were established according to the theory of infrared physics and heat conduction, and then the dynamic infrared image was generated by OpenGL. The last step is to obtain the distortion Image with turbulence atmospheric transmission effects .With the data of atmospheric transmission computation, infrared simulation image of every frame was processed according to the theory of image processing and the real-time image simulation, and then the dynamic distortion simulation images with effects of blurring, jitter and shifting were obtained. Above-mentioned simulation method can provide the theoretical bases for recovering the blur images and analyzing the turbulence atmospheric transmission effects.

In the process of high-resolution astronomical observation and space optical mapping, the wavefront aberrations caused by atmosphere turbulence effect lead to reduced resolution of optical imaging sensor. Firstly, on the base of influence of atmosphere turbulence effect for the optical observation system, this paper investigates and analyses the development and technical characteristics of deformable mirror, which is the key device of optical wavefront control technology. In this part, the paper describes the basic principles of wavefront control and measurement using the current production line of deformable mirror, including micro-electromechanical systems (MEMS) deformable mirror which is one of the most promising technology for wavefront modulation and Shack-Hartmann wavefront sensors. Secondly, a new method based on the technology of optical wavefront control and the data of optical path difference (OPD) for simulating the effect of optical transmission induced by turbulence is presented in this paper. The modeling and characteristics of atmosphere turbulence effect applied for optical imagery detector of astronomical observation and space optical mapping has been obtained. Finally, based on the theory model of atmosphere turbulence effects and digital simulation results, a preliminary experiment was done and the results verify the feasibility of the new method. The OPD data corresponding to optical propagation effect through turbulent atmosphere can be achieved by the calculation based on the method of ray-tracing and principle of physical optics. It is a common practice to decompose aberrated wavefronts in series over the Zernike polynomials. These data will be applied to the drive and control of the deformable mirror. This kind of simulation method can be applied to simulate the optical distortions effect, such as the dithering and excursion of light spot, in the space based earth observation with the influence of turbulent atmosphere. With the help of the optical wavefront control technology, the optical sensor and ability of space optical detection system for correcting the target image blurred by turbulence of atmosphere can be tested and evaluated in the laboratory.

With the consumption of the resources, it’s important to develop clean solar energy that can solve the problem of energy shortage. Obtaining an accurate position of the sun is the premise of using the solar energy efficiently. An accurate solar position includes two factors that are elevation and azimuth. In the paper, Joseph J. Michalsky’s algorithm for calculation of the solar position is verified that is taken from the American Astronomical Almanac. The algorithm has been written into program by Joseph J. Michalsky in FORTRAN. In the paper, it’s has been adapted to visual C++ that can calculate the solar elevation and azimuth and errors or some places that less accurate are corrected. The Chinese Astronomical Almanac for the year 1985 doesn’t tabulate elevation and azimuth. The quantities needed to calculate elevation and azimuth are the right ascension, the declination and the Greenwich mean sidereal time that are tabulated in the Almanac. Comparing those variables that calculated from the algorithm with the data from the Chinese Astronomical Almanac for the year 1985, it can be found that the biggest difference of the two ways is only 0.01°, 0.01° and 0.0001h respectively, which prove the accuracy of the algorithm indirectly. The measured data that only include elevation comes from Basic Data of Geography in China written by Institute of Geography, Chinese Academy of Sciences. Comparing elevation given by the algorithm with the measured data, it shows that the algorithm can be accurate calculating the position of the sun in some extent. And the paper shows in detail the conversion from the local real solar time to Universal Time because the time in Basic Data of Geography in China is the local real solar time. Finally we notice that the 0.01° accuracy mentioned by other paper is not the accuracy of the elevation and azimuth of the sun, but the accuracy of the right ascension and declination. It’s easy to understand why the difference of the results calculated by the algorithm and measured data is greater than 0.01°.

With the rapid development of computer technology and mobile devices, high requirements for computer vision are more and more critical. In particular, current research on moving target detection based on still scene or hardware platform with turntable and gyroscope, can not meet the requirements of portable mobile equipment. Moving target detection and tracking on mobile platforms is attracting more and more attention. What makes the task even more challenging is when the camera is non-stationary ,due to the random motion of camera caused by bumps and swings of vehicle and handheld, and parallax problem caused by 3D scene. The essential problem in this case lies in distinguishing between global motion induced by camera and independent motion caused by moving targets. To solve above problems, the three-dimensional reconstruction method based on camera calibration technology is always introduced, such as the fundamental matrix and trifocal tensor, but that are appropriate for large classes of problems and situations without considering the complexity and speed of processing. This paper proposes a new robust algorithm GMOS (Global Motion Of Scene) based on the global motion of scene for moving object detection on a freely moving camera. By modeling for GMOS with the adjacent optical flow field of the image sequence, the proposed method is able to detect and separate the moving targets simply and fast from the global motion model without three-dimensional reconstruction. According to the GMOS model, we can describe the movement of the camera through a GMOS vector which is independent of two viewpoints between the adjacent images, and compensate for the overall movement caused by camera movement. The results of theory analysis and experimentations on numerous real world videos demonstrate that the proposed method GMOS could separate the independent objects fast and robustly under the premise of the high accuracy and robustness.

In the practical application of infrared lasers, an infrared linear laser beam of 90°×2° is shaped to meet special demand. So it is very important to test its beam divergence angle which reflects long-distance transmission characteristics. Many approaches are proposed, such as area array CCD single imaging method, two plate reflecting mirrors multi imaging method, distorted diffraction grating multi imaging method and so on. Nevertheless, these methods only can be used to detect infrared laser beam whose spot shape is small and elliptical. Actually if the view angle of the infrared linear laser beam is greater than 90° in the horizontal direction, the area array CCD cannot detect the whole light spot. So we proposed a two linear array CCDs scanning imaging measurement method. The two linear array CCDs are placed at Z₁ position of near field and Z₂ position of far field respectively, and they are separated by an angle Φ. Beam width in two positions can be calculated by light intensity distribution curves which are measured by linear array CCD. Meanwhile, beam width fits linear equation in the far field, so beam divergence angle can be obtained by two point line fitting. This method is based on a real-time and automatic measurement system which consists of infrared laser optical transmitter, control module, imaging system and data processing. The infrared laser optical transmitter is controlled by control module to rotate every one degree. After scanning is completed, we can acquire the spot image and beam divergence angle curve by imaging system and data processing. This novel arrangement provides a precise and comprehensive measurement. Compared to other methods, this method can not only be used for measuring beam divergence angle of infrared linear laser beam, but also for detecting the uniformity of energy distribution and assembling laser optical transmitter. Experimental results indicate that measurement values are in the acceptable range, measurement accuracy is 1', and repeatability precision is 2.36%. Theory analysis and experiment shows the method is reasonable and efficient.

X-ray security device cannot detect accurately for some volatile of toxic harmful or flammable easy explosion products, this article takes electronic noses as secondary detection means of x-ray security equipment embedded in the x-ray security equipment. Using different mode recognition methods process experimental data, focus research on neural network mode recognition method, last established effective BP network model, identification accurate rate is 100% for gas species. Take the X-ray detection technology and electronic nose odor recognition technology combination to achieve the integration of multi-testing information, provide effective methods and theoretical basis for research and development of new security equipment, and realize the integration of a variety of information technology and multi-stage checking.

The threat of the IR guidance missile is a direct consequence of extensive proliferation of the airborne IR countermeasure. The aim of a countermeasure system is to inject false information into a sensor system to create confusion. Many optical seekers have a single detector that is used to sense the position of its victim in its field of view. A seeker has a spinning reticle in the focal plane of the optical system that collects energy from the thermal scene and focuses it on to the detector. In this paper, the principle of the conical-scan FM reticle is analyzed. Then the effect that different amplitude or frequency modulated mid-infrared laser pulse acts on the reticle system is simulated. When the ratio of jamming energy to target radiation (repression) gradually increases, the azimuth error and the misalignment angle error become larger. The results show that simply increasing the intensity of the jamming light achieves little, but it increases the received signal strength of the FM reticle system ,so that the target will be more easily exposed. A slow variation of amplitude will warp the azimuth information received by the seeker, but the target can’t be completely out of the missile tracking. If the repression and the jamming frequency change at the same time, the jamming effects can be more obvious. When the jamming signal’s angular frequency is twice as large as the carrier frequency of the reticle system, the seeker will can’t receive an accurate signal and the jamming can be achieved. The jamming mechanism of the conical-scan FM IR seeker is described and it is helpful to the airborne IR countermeasure system.

The paper is committed in local image enhancement. At first, the authors propose an adjacent pixel gray order-preserving principle. Adjacent pixel gray order-preserving principle is the basement of local enhancement method which ensures that there is no distortion in processed image. And then, the authors propose an iterative algorithm, which could stretch gray-scale difference of adjacent pixels in premise of not changing gray magnitude relationship between adjacent pixels. At last, the authors propose a totally reference image quality assessment method based on adjacent pixel gray order-preserving principle. According to this quality assessment method, the authors made a set of comparative experiments with local histogram equalization and method. Experimental results show that the proposed enhancement method can get higher score and provide better visual effects, fully demonstrating its effectiveness. According to this quality assessment method, the proposed method shows a good effectiveness, through experimental results and comparison with local histogram equalization method. Local contrast enhancement, adjacent pixel gray order-preserving principle, iterative algorithm, image quality assessment.

For counteracting background current of photoconductive (PC) PbS detector, an example of layout design and analyze 1×128 linear PbS infrared focal plane array (IRFPA) detector using resistance selection of blind sensitive element is given. 1×128 linear PC PbS infrared focal plane array detector is fabricated and characterized by IRFPA test-bench. Results show that average responsivity of detector is 4.19×10⁶V/W; average detectivity of detector is 5.79×10⁹cm•Hz^1/2•W^-1.

Mean shift, which is widely used in many target tracking systems, is a very effective algorithm to track the target. But the traditional mean shift tracking algorithm is limited to track an infrared small target. In infrared prewarning and tracking systems, the traditional mean shift tracking algorithm cannot achieve accurate tracking result due to that the target is weakened and submerged in the background noise. So in this paper, a compositive mean shift algorithm is put forward. In this algorithm, firstly on the basis of background suppression and division, noise is suppressed by an extraordinary Robinson Guard Filter. This paper adopts a dual patterns merging Robinson Guard Filter which is different from the traditional Robinson Guard Filter. According to the point target’s anisotropic singularity in space, this dual patterns merging Robinson Guard Filter can divide the direction further and detect singularity accurately in different directions in order to obtain better effect. The dual patterns merging Robinson Guard Filter’s improvement is that it adopts the horizontal and vertical direction window and the diagonal direction window whose protective belt width are both two at the same time to increase the probability of point target detection. The filter separately detects the two directions and merges the results in order to boost the effect of keeping back the details of the target. At the same time, it can also boost the effect of background suppression as much as possible and reduce the false alarm rate. At last the system can achieve ideal detection performance. After filtering, an image in which the point target and the background are distinguished is acquired. Then in the mean shift algorithm, we use the acquired image for target tracking. The results of experiment show that this improved mean shift algorithm can reduce failure probability of prewarning and track infrared small targets steadily and accurately.

A flat structure element is usually used in the traditional morphological detection. In this processing method, the infrared target is regarded as a single point without considering the imaging characteristics of infrared dim and small target. There is a gray transition zone between target and background. It is unreasonable that the transition region processed as background in the traditional morphological method. So, the infrared dim target detection results are not ideal by using the traditional morphological processing method. Aimed at this problem, the imaging characteristic of infrared dim and small target is analyzed. The Spatial distribution of infrared target gray scale is calculated. The result shows it is a tip package structure. The top peak is the target. Based on theoretical research on the morphological detection, the girdle structure elements are designed. This structure is composed of two circles. The target neighborhood zones are protected in this structure. They do not participate in the morphological calculation. The sixteen external zones are only participated in the calculation. The morphology of infrared target detection method is established based on this neighborhood zoned structure. The designed girdle structure is used in the opening operation and the traditional flat structure is used in the closing operation. The traditional Top-Hat algorithm is improved according to the girdle structure morphology method. And used the real infrared target image, the improved algorithm is simulated. The processed result shows that the girdle structure morphology method is effective in the background noise restraining. In order to evaluate the image processed result quantitatively, the signal noise ratio and signal noise ratio gain factor are used. Accordingly to the calculated result, the improved algorithm compared with the traditional morphological methods, inhibition of complex background with better.

Reliable modeling for thermal infrared (IR) signatures of real-world city scenes is required for signature management of civil and military platforms. Traditional modeling methods generally assume that scene objects are individual entities during the physical processes occurring in infrared range. However, in reality, the physical scene involves convective and conductive interactions between objects as well as the radiations interactions between objects. A method based on radiosity model describes these complex effects. It has been developed to enable an accurate simulation for the radiance distribution of the city scenes. Firstly, the physical processes affecting the IR characteristic of city scenes were described. Secondly, heat balance equations were formed on the basis of combining the atmospheric conditions, shadow maps and the geometry of scene. Finally, finite difference method was used to calculate the kinetic temperature of object surface. A radiosity model was introduced to describe the scattering effect of radiation between surface elements in the scene. By the synthesis of objects radiance distribution in infrared range, we could obtain the IR characteristic of scene. Real infrared images and model predictions were shown and compared. The results demonstrate that this method can realistically simulate the IR characteristic of city scenes. It effectively displays the infrared shadow effects and the radiation interactions between objects in city scenes.

SIFT registration can obtain scale invariant and rotation invariant features easily. SIFT requires images with rich details, and the amount of calculation is too large. SIFT for infrared image and visible image registration, discarded the edge features and the low contrast pixels directly. Especially when the image with low contrast in sea and sky background, SIFT registration cannot get enough feature points and desirable effects. The classic SIFT algorithm often result in feature point degradation. A novel approach has been proposed, which through the most stable extremely region flock the SIFT feature points. Analysis the worth of low contrast and edge information in sea and sky background image, use it to rough registration. Comparison of the algorithm with an algorithm of the same kind, the results show the effectiveness of the registration with low ergodic comparisons.

The infrared radiation signature of exhaust plume from solid propellant rockets has been widely mentioned for its important realistic meaning. The content of aluminum powder in the propellants is a key factor that affects the infrared radiation signature of the plume. The related studies are mostly on the conical nozzles. In this paper, the influence of aluminum on the flow field of plume, temperature distribution, and the infrared radiation characteristics were numerically studied with an object of 3D quadrate nozzle. Firstly, the gas phase flow field and gas-solid multi phase flow filed of the exhaust plume were calculated using CFD method. The result indicates that the Al₂0₃ particles have significant effect on the flow field of plume. Secondly, the radiation transfer equation was solved by using a discrete coordinate method. The spectral radiation intensity from 1000-2400 cm^-1 was obtained. To study the infrared radiation characteristics of exhaust plume, an exceptional quadrate nozzle was employed and much attention was paid to the influences of Al₂0₃ particles in solid propellants. The results could dedicate the design of the divert control motor in such hypervelocity interceptors or missiles, or be of certain meaning to the improvement of ingredients of solid propellants.

Based on the aliasing theory of focal plane array (FPA) thermal imaging systems, aliasing as noise (AAN) method and under-sampling system evaluation model based on information theory (EMIT) were analyzed. The aliasing was treated as one kind of noise and introduced into minimum resolvable temperature difference (MRTD) model, and the integral expressing of aliasing signal (IAS) method was proposed to evaluate the impact of aliasing on the performance of thermal imaging systems. IAS method was proved to be able to describe the impact of aliasing grade on the system performance effectively. The three MRTD models with different aliasing evaluation methods were researched contrastively by MRTD test experiment and target detection probability experiment. The MRTD model with IAS method was proved to evaluate the performance of under-sampling thermal imaging systems effectively, and could be used in the performance prediction of thermal imaging systems. In the future, the precision of IAS method will be researched further.

The impact of nature environment on the synthesized performance of thermal imaging systems was researched comparing with the targeting task performance (TTP) model. A nature background noise factor was presented and introduced into the minimum resolvable temperature difference channel width (MRTD-CW) model. The method for determining the nature background noise factor was given. A information quantity model based on MRTD-CW model was proposed to evaluate the impact of nature environment on the synthesized performance of thermal imaging systems. A normalized parameter was introduced into the information quantity model. Different background experiments were performed, and the results were analyzed and compared with those of TTP model.

According to infrared imaging features of forest fire, we use image processing technology which is conducive to early detection and prevention of forest fires. We use image processing technology based on infrared imaging features of forest fire which is conducive to early detection and prevention of forest fires. In order to the timeliness and accuracy of fire detection, this paper proposes a forest fire detection method based on infrared image technology. We take gray histogram analysis to collected Cruising image. The image which will be detected is segmented by the adaptive dynamic threshold. Then the suspected ignitions are extracted in the image after segmentation. The ignition of forest fire which form image in the infrared image is almost circular. We use the circular degree of suspected ignition as the decision basis of the fire in the infrared image. Through the analysis of position correlation which is the same suspected ignition between adjacent frames, we judge whether there is a fire in the image. In order to verify the effectiveness of the method, we adopt image sequences of forest fire to do experiment. The experimental results show that the proposed algorithm under the conditions of different light conditions and complex backgrounds, which can effectively eliminate distractions and extract the fire target. The accuracy fire detection rate is above 95 percent. All fire can be detected. The method can quickly identify fire flame and high-risk points of early fire. The structure of method is clear and efficient which processing speed is less than 25 frames per second. So it meets the application requirement of real-time processing.

Local invariant feature extraction, as one of the main problems in the field of computer vision, has been widely applied to image matching, splicing and target recognition etc. Lowe’s scale invariant feature transform (known as SIFT) algorithm has attracted much attention due to its invariance to scale, rotation and illumination. However, SIFT is not robust to affine deformations, because it is based on the DoG detector which extracts keypoints in a circle region. Besides, the feature descriptor is represented by a 128-dimensional vector, which means that the algorithm complexity is extremely large especially when there is a great quantity of keypoints in the image. In this paper, a new feature descriptor, which is robust to affine deformations, is proposed. Considering that circles turn to be ellipses after affine deformations, some improvements have been made. Firstly, the Gaussian image pyramids are constructed by convoluting the source image and the elliptical Gaussian kernel with two volatile parameters, orientation and eccentricity. In addition, the two parameters are discretely selected in order to imitate the possibilities of the affine deformation, which can make sure that anisotropic regions are transformed into isotropic ones. Next, all extreme points can be extracted as the candidates for the affine-invariant keypoints in the image pyramids. After accurate keypoints localization is performed, the secondary moment of the keypoints’ neighborhood is calculated to identify the elliptical region which is affineinvariant, the same as SIFT, the main orientation of the keypoints can be determined and the feature descriptor is generated based on the histogram constructed in this region. At last, the PCA method for the 128-dimensional descriptor’s reduction is used to improve the computer calculating efficiency. The experiments show that this new algorithm inherits all SIFT’s original advantages, and has a good resistance to affine deformations; what’s more, it is more effective in calculation and storage requirement.

In this paper we follow the concept of the track before detect (TBD) category in order to perform a simple, fast and adaptive detection and tracking processes of dim pixel size moving targets in IR images sequence. We present two new algorithms based on an image frames transformation, the first algorithm is a recursive algorithm to measure the image background Baseline which help in assigning an adaptive threshold, while the second is an adaptive recursive statistical spatio-temporal algorithm for detecting and tracking the target. The results of applying the proposed algorithms on a set of frames having a simple single pixel target performing a linear motion shows a high efficiency and validity in the detecting of the motion, and the measurement of the background baseline.

Conventional passive thermal design failed to satisfy CCD’s temperature requirement on a geostationary earth orbit satellite Imager camera because of the high power and low working temperature, leading to utilization of thermoelectric cooler (TEC) for heat dissipation. TEC was used in conjunction with the external radiator in the CCDs’ thermal design. In order to maintain the CCDs at low working temperature, experimental research on the performance of thermoelectric cooler was necessary and the results could be the guide for the application of TEC in different conditions. The experimental system to evaluate the performance of TEC was designed and built, consisting of TEC, heat pipe, TEC mounting plate, radiator and heater. A series of TEC performance tests were conducted for domestic and oversea TECs in thermal vacuum environment. The effects of TEC’s mounting, input power and heat load on the temperature difference of TEC’s cold and hot face were explored. Results demonstrated that the temperature difference of TEC’s cold and hot face was slightly increased when TEC’s operating voltage reached 80% of rating voltage, which caused the temperature rise of TEC’s hot face. It recommended TEC to operate at low voltage. Based on experiment results, thermal analysis indicated that the temperature difference of TEC’s cold and hot face could satisfy the temperature requirement and still had surplus.

An approach to infrared ship detection based on sea-sky-line(SSL) detection, ROI extraction and feature recognition is proposed in this paper. Firstly, considering that far ships are expected to be adjacent to the SSL, SSL is detected to find potential target areas. Radon transform is performed on gradient image to choose candidate SSLs, and detection result is given by fuzzy synthetic evaluation values. Secondly, in view of recognizable condition that there should be enough differences between target and background in infrared image, two gradient masks have been created and improved as practical guidelines in eliminating false alarm. Thirdly, extract ROI near the SSL by using multi-grade segmentation and fusion method after image sharpening, and unsuitable candidates are screened out according to the gradient masks and ROI shape. Finally, we segment the rest of ROIs by two-stage modified OTSU, and calculate target confidence as a standard measuring the facticity of target. Compared with other ship detection methods, proposed method is suitable for bipolar targets, which offers a good practicability and accuracy, and achieves a satisfying detection speed. Detection experiments with 200 thousand frames show that the proposed method is widely applicable, powerful in resistance to interferences and noises with a detection rate of above 95%, which satisfies the engineering needs commendably.

In order to improve the precision of optical-electric tracking device, proposing a kind of improved optical-electric tracking device based on MEMS, in allusion to the tracking error of gyroscope senor and the random drift, According to the principles of time series analysis of random sequence, establish AR model of gyro random error based on Kalman filter algorithm, then the output signals of gyro are multiple filtered with Kalman filter. And use ARM as micro controller servo motor is controlled by fuzzy PID full closed loop control algorithm, and add advanced correction and feed-forward links to improve response lag of angle input, Free-forward can make output perfectly follow input. The function of lead compensation link is to shorten the response of input signals, so as to reduce errors. Use the wireless video monitor module and remote monitoring software (Visual Basic 6.0) to monitor servo motor state in real time, the video monitor module gathers video signals, and the wireless video module will sent these signals to upper computer, so that show the motor running state in the window of Visual Basic 6.0. At the same time, take a detailed analysis to the main error source. Through the quantitative analysis of the errors from bandwidth and gyro sensor, it makes the proportion of each error in the whole error more intuitive, consequently, decrease the error of the system. Through the simulation and experiment results shows the system has good following characteristic, and it is very valuable for engineering application.

There exist complex gray mapping relationships among infrared and visible images because of the different imaging mechanisms. The difficulty of infrared and visible image registration is to find a reasonable similarity definition. In this paper, we develop a novel image similarity called implicit line segment similarity(ILS) and a registration algorithm of infrared and visible images based on ILS. Essentially, the algorithm achieves image registration by aligning the corresponding line segment features in two images. First, we extract line segment features and record their coordinate positions in one of the images, and map these line segments into the second image based on the geometric transformation model. Then we iteratively maximize the degree of similarity between the line segment features and correspondence regions in the second image to obtain the model parameters. The advantage of doing this is no need directly measuring the gray similarity between the two images. We adopt a multi-resolution analysis method to calculate the model parameters from coarse to fine on Gaussian scale space. The geometric transformation parameters are finally obtained by the improved Powell algorithm. Comparative experiments demonstrate that the proposed algorithm can effectively achieve the automatic registration for infrared and visible images, and under considerable accuracy it makes a more significant improvement on computational efficiency and anti-noise ability than previously proposed algorithms.

Signal-to-noise ratio (SNR) is an important parameter of infrared detection system. SNR of infrared detection system is determined by the target infrared radiation, atmospheric transmittance, background infrared radiation and the detector noise. The infrared radiation flux in the atmosphere is determined by the selective absorption of the gas molecules, the atmospheric environment, and the transmission distance of the radiation, etc, so the atmospheric transmittance and infrared radiance flux are intricate parameters. A radiometric model for the calculation of SNR of infrared detection system is developed and used to evaluate the effects of various parameters on signal-to-noise ratio (SNR). An atmospheric modeling tool, MODTRAN, is used to model wavelength-dependent atmospheric transmission and sky background radiance. Then a new expression of SNR is deduced. Instead of using constants such as average atmospheric transmission and average wavelength in traditional method, it uses discrete values for atmospheric transmission and sky background radiance. The integrals in general expression of SNR are converted to summations. The accuracy of SNR obtained from the new method can be improved. By adopting atmospheric condition of the 1976 US standard, no clouds urban aerosols, fall-winter aerosol profiles, the typical spectrum characters of sky background radiance and transmittance are computed by MODTRON. Then the operating ranges corresponding to the threshold quantity of SNR are calculated with the new method. The calculated operating ranges are more close to the measured operating range than those calculated with the traditional method.

7.5 ~ 9.7μm traditional wide band antireflective (AR) film is designed on ZnS, choosing Ge, ZnS and YF₃ as film material, and the average transmittance (T) could be elevated from 74.9% to 98% when AOI=0°. But while AOI=70°, T of p and s component is 85.9% and 75.6% separately, and the average transmittance is 80.8% because of the separation of s- and p-polarized light. Depolarization antireflective film is also designed with the same materials by equivalent-layer method to balance s- and p- component energy, and the polarization effect at different incident angles is analyzed. When AOI=0°, T is 99.3%, and when AOI=70°, T is 90.6%, 10% less than that of traditional AR film. So equivalent-layer method is effective to eliminate polarization effect of broadband antireflective coatings at large incident angle and then could effectively improve the optical performance, which is critical in precision guide system.

This paper proposed a new algorithm of inter-frame filtering in IR image based on threshold value for the purpose of solving image blur and smear brought by traditional inter-frame filtering algorithm. At first, it finds out causes of image blur and smear by analyzing general inter-frame filtering algorithm and dynamic inter-frame filtering algorithm, hence to bring up a new kind of time-domain filter. In order to obtain coefficients of the filter, it firstly gets difference image of present image and previous image, and then, it gets noisy threshold value by analyzing difference image with probability analysis method. The relationship between difference image and threshold value helps obtaining the coefficients of filter. At last, inter-frame filtering method is adopted to process pixels interrupted by noise. The experimental result shows that this algorithm has successfully repressed IR image blur and smear, and NETD tested by traditional inter filtering algorithm and the new algorithm are respectively 78mK and 70mK, which shows it has a better noise reduction performance than traditional ones. The algorithm is not only applied to still image, but also to sports image. As a new algorithm with great practical value, it is easy to achieve on FPGA, of excellent real-time performance and it effectively extends application scope of time domain filtering algorithm.

For accurate knowledge of the impact of ejector technique on infrared radiation of the plume, the physical model of the rectangular nozzle is established. The 3-D flow field outside the rectangular nozzle is simulated by numerical method with software Fluent6.3 pre and post the application of ejector technique, then the data of the flow fields, such as temperature, pressure and density and so on, are obtained, and according to the characteristic of the rectangular nozzle plume the computational domain of infrared radiation was established. This paper uses Lorentz linear statistical narrow-band model to calculate the mean absorption coefficient of the plume in the narrow band. Then it uses Finite Volume Method(FVM) to solve the radiation transmission equations in gas medium, and it obtains the total intensity distribution in 3~5μm of the plume radiation pre and post the application of ejector technique. The results shows that the infrared radiant of the rectangular nozzle decreases significantly by 80% after the application of ejector technique.

In recent years, the weapon systems of laser guidance and infrared (IR) imaging guidance have been widely used in modern warfare because of their high precision and strong anti-interference. Notwithstanding, military smoke, as a rapid and effective passive jamming means, can effectively counteract the attack of enemy precision-guided weapons by scattering and absorbability. Conventional smoke has good attenuation capability only to visible light (0.4-0.76 μm), but hardly any effect to other electromagnetic wave band. The weapon systems of laser guidance and IR imaging guidance usually work in broad band, including near IR (1-3 μm), middle IR (3-5 μm), far IR (8-14 μm), and so on. Accordingly, exploiting and using new efficient obscurant materials, which is one of the important factors that develop smoke technology, have become a focus and attracted more interests around the world. Then nano-structured materials that are developing very quickly have turned into our new choice. Hollow nano-structured materials (HNSM) have many special properties because of their nano-size wall-thickness and sub-micron grain-size. After a lot of HNSM were synthesized in this paper, their physical and chemical properties, including grain size, phase composition, microstructure, optical properties and resistivity were tested and analysed. Then the experimental results of the optical properties showed that HNSM exhibit excellent wave-absorbing ability in ultraviolet, visible and infrared regions. On the basis of the physicochemmical properties, HNSM are firstly applied in smoke technology field. And the obscuration performance of HNSM smoke was tested in smoke chamber. The testing waveband included 1.06μm and 10.6μm laser, 3-5μm and 8-14μm IR radiation. Then the main parameters were obtained, including the attenuation rate, the transmission rate, the mass extinction coefficient, the efficiency obscuring time, and the sedimentation rate, etc. The main parameters of HNSM smoke were contrasted in detail with graphite powder smoke agent. The results showed that HNSM smoke possesses better obscuration capability compared with the smoke performance of conventional materials (such as HC, RP, oil, carbon black, and graphite powder). Therefore, they are new smoke obscurant materials which can effectively interfere with broadband electromagnetic radiation, including 1.06 μm and 10.6 μm laser, 3-5 μm and 8-14 μm IR waveband.

The Infrared radiation characteristic research of high temperature target has an important role in the field of target recognition and tracking, etc. Affected by atmosphere, background environment and spatial resolution, the recognition to smaller thermal targets have certain limitations. This paper used two sensitive spectral intervals to high temperature object feature and used MODTRAN5.0 quantitative analyze infrared radiation energy of the heat target in the atmosphere into the pupil of the remote sensor. And this paper adopted the statistics method to analyze the sensitivity of the radiance results of the heterotherm and allohypsic targets under the condition of a very different enrage background. Simulation results compared with the results from Line by line integral model calculating HITRAN database using FASCODE model in the given same condition. The comparison results show the method in this article can be used fast and convenient to calculate high temperature target radiance and improve the recognition of high temperature target.

Scene-based nonuniformity correction technique for Infrared focal-plane array has been widely concerned as a key technology. However, the existed algorithms are now facing two major problems that is convergence speed and ghosting artifacts. The convergence speed of original constant statistics (CS) method has been demonstrated to be more rapidly than the neural network method but how to reduce ghosting artifacts efficiently is the largest challenge. To solve the ghosting problem, the conventional methods often set a threshold to wipe off the outliers, but the threshold is difficult to choose because it changes complexly for different scene. In this paper, a novel adaptive scene-based nonuniformity correction technique is presented that performs the nonuniformity correction based on CS method. Firstly, an analysis of statistical characteristic in every pixel is taken and the cause of ghosting artifacts is discussed that the underlying distribution does not satisfy the assumptions such as symmetry. For the Gaussian distribution can not describe the statistic property for every pixel’s data, a model with mixture distribution is constructed and indicates the different distribution’s influence to generate ghosting artifacts. Then, utilizing temporal statistics of infrared image sequences the proposed method applies an alpha-trimmed mean filter to estimate detector parameters instead of the conventional mean filter. The algorithm selects the parameter of the alpha-trimmed mean estimator optimally with minimizing the sample asymptotic variance estimate. Moreover, the alpha-trimmed mean filter is designed to detect the nonsymmetry points and trim out the outlier pixels such as edges or extreme distribution. Finally, the performance of the proposed algorithm is evaluated with infrared image sequences with simulated and real fixed-pattern noise. Compared with other nonuniformity correction techniques, the proposed method inherits the superiority of the CS method that converges rapidly but is more robust and gets little ghosting artifacts. The results of the simulated and the real infrared images experiments show a significantly more reliable ability to compensate for nonuniformity and reducing ghosting artifacts effectively.

Infrared imaging system has been used widely for its ability of working day and night. The performance of dim target detection is one important performance guideline for many applications, such as surveillance system, alarm system, searching and rescuing system, and so on. Multi-spectral infrared image fusion could help to get more information by complementing difference from different wave band images. One method was proposed to realize the dim target detection based on image fusion by using one character filter in transformational domain in the process of image fusion to enhance target and constrain background in fused image. The experimental results demonstrate that proposed method increased the ratio of target-to-background in fused image, and improved the probability of target detection and reduced the probability of false alarm on noisy infrared images.

Traditional bad pixel detection algorithm is always based on the radiometric calibration. This method is easy to operate, but only suitable for the bad pixels whose positions are fixed. During the longtime operation period, environment temperature usually has drastic influence on IRFPA, the number of bad pixels often increase and their positions also vary, this result in the degradation of infrared image quality. In this paper, a new scene-based adaptive bad pixel detection algorithm is proposed for IRFPA. The algorithm firstly comparing the pixel value with its neighborhood, and affirm bad pixels preliminary through a suitable threshold. Then the potential bad pixels from different scene are matched, false bad pixels caused by scene and targets are eliminated, real bad pixels are confirmed. The essence of the proposed algorithm is using the correlation between the pixel and its neighborhood. The bad pixels and some targets in the scene have a weak correlation within neighborhoods, and the position of bad pixels varies slowly while the scene varies drastically when IRFPA is in use. This new method can be implemented in hardware easily and achieve the real time demand. With the real infrared images obtained from a camera, the experiment results show the effectiveness of the proposed algorithm.

Optical systems for scientific instrumentation frequently include lens or mirrors with critical mechanical requirements. Position issues of those components are inextricably bound to the efficiency of the instrument. The position referring to the lens system mainly means spacer and rotation of all elements concerned. Instrument could not be completed without the accuracy assembly even the previous design was top one. The alignment of infrared optical system always is a tough thing due to the IR material being opaque to visible light which hardly effect on the imaging ability of the system. In this paper a large-aperture IR refractive system was described in details and the alignment of this system was presented. The brief work describes the assembly and integration of the camera barrel in lab. First of all, all the mechanical elements must be manufactured with high accuracy requirements to meet alignment tolerances and minimum errors mostly could be ignored. The rotations relative to the optical axis were hardy restricted by the space between barrel and cells. The lens vertex displacements were determined through high accuracy titanium alloy spacer. So the actual shape data of the optical lenses were obtained by coordinate measuring machining (CMM) to calculate the real space between lenses after alignment1 done. All the measured results were critical for instruction of the practical assemble. Based on the properties and tolerances of the system, the camera barrel includes sets of six lenses with their respective supports and cells which are composed of two parts: the flied lens group and the relay lenses group. The first one was aligned by the geometry centering used CMM. And the relay lenses were integrated one by one after centered individually with a classical centering instrument. Then the two separate components were assembled under the monitor of the CMM with micron precision. Three parameters on the opti-mechanical elements which include decenter, tilt and space changing along the optical axis were measured and determined the relative position of the two components. Finally, the integrated system was verified and results showed that alignment met the design requirement.

The infrared (IR) imaging missile’s dome will be heated when fly at high speed in the atmosphere because of the friction of the air flow blocking. The detector’s performance will be decline if the dome surface is heated to a certain temperature. In this paper, we find a right way to evaluate the aerothermal effects in the imaging and information processing algorithm. Which have three steps including the aerothermal radiation calculation, quantization and image reconstruction. Firstly, the aerothermal radiation is calculated by using a combination of both methods of theoretical analysis and experiment data. Secondly, the relationship between aerothermal radiation and IR images background mean gray and noise can be calculated through the analysis of the experiment data. At last, we can rebuild an aerodynamic heating effect of infrared images fusion with target and decoy, which can be used for virtual prototyping platform missile trajectory simulation. It can be found that the above constructed images have good agreements with the actual image according to comparison between the simulation data and experiment data. It is an economic method that can solve the lab aerodynamic heating simulation and modeling problems.

In infrared image, the grey distribution of background and target are instability, so it has much difficulty in the target segmentation. In this paper, a novel image segmentation algorithm is presented which is based on Contourlet transform and background complexity. Firstly, using Contourlet transform, the structure information of target and background is obtained. Next, structure similarity of target and background is computed. Finally, through the structure similarity of target and background, segmentation threshold is adjusted adaptively. If the structure similarity of target and background is low, it indicates that background is simple, segmentation threshold is set with the grey information. If the structure similarity of target and background is high, segmentation threshold is set with the structure information. The simulation experiments show that the target can be segmented truly in the complex background environment. The algorithm not only reserves the advantage of the grey segmentation in simple background environment, but overcomes the limitation of the grey segmentation in complex background environment, shows better adaptability than the traditional image segmentation methods.

Indium tin oxide (ITO) films were deposited on sapphire substrates at temperatures ranging from 30°C to 700°C and oxygen background pressure changing from 0.05 Pa to 0.25 Pa by femtosecond pulsed laser deposition (PLD). The films were characterized using metallurgical microscope, film resistance meter and Fourier transform infrared spectrometer to study the effect of substrate temperature and oxygen background pressure on the surface topography, sheet resistance and infrared transmission. The photographs of metallurgical microscope show that substrate temperature plays a dominant role on the surface morphology of the films. The sheet resistance test suggests that the sheet resistance of the film decreases with increase of substrate temperature but increases with increase of oxygen background pressure. The results of infrared transmission show that the infrared transmission through the ITO film is about 40% at the wavelength of 1.5μm to 1.8μm and is very low at other infrared band. The films deposited at higher substrate temperatures show lower value of transmittance, and which at higher oxygen background pressure show higher value of transmittance.

The diffuse reflection type of omni-directional laser warning based on fish-eye lens is becoming more and more important. As one of the key parameters of warning system, the warning radius should be put into investigation emphatically. The paper firstly theoretically analyzes the energy detected by single pixel of FPA detector in the system under complicated environment. Then the least energy detectable by each single pixel of the system is computed in terms of detector sensitivity, system noise, and minimum SNR. Subsequently, by comparison between the energy detected by single pixel and the least detectable energy, the warning radius is deduced from Torrance-Sparrow five-parameter semiempirical statistic model. Finally, a field experiment was developed to validate the computational results. It has been found that the warning radius has a close relationship with BRDF parameters of the irradiated target, propagation distance, angle of incidence, and detector sensitivity, etc. Furthermore, an important fact is shown that the experimental values of warning radius are always less than that of theoretical ones, due to such factors as the optical aberration of fish-eye lens, the transmissivity of narrowband filter, and the packing ratio of detector.

Biometric signatures for identity recognition have been practiced for centuries. Basically, the personal attributes used for a biometric identification system can be classified into two areas: one is based on physiological attributes, such as DNA, facial features, retinal vasculature, fingerprint, hand geometry, iris texture and so on; the other scenario is dependent on the individual behavioral attributes, such as signature, keystroke, voice and gait style. Among these features, iris recognition is one of the most attractive approaches due to its nature of randomness, texture stability over a life time, high entropy density and non-invasive acquisition. While the performance of iris recognition on high quality image is well investigated, not too many studies addressed that how iris recognition performs subject to non-ideal image data, especially when the data is acquired in challenging conditions, such as long working distance, dynamical movement of subjects, uncontrolled illumination conditions and so on. There are three main contributions in this paper. Firstly, the optical system parameters, such as magnification and field of view, was optimally designed through the first-order optics. Secondly, the irradiance constraints was derived by optical conservation theorem. Through the relationship between the subject and the detector, we could estimate the limitation of working distance when the camera lens and CCD sensor were known. The working distance is set to 3m in our system with pupil diameter 86mm and CCD irradiance 0.3mW/cm². Finally, We employed a hybrid scheme combining eye tracking with pan and tilt system, wavefront coding technology, filter optimization and post signal recognition to implement a robust iris recognition system in dynamic operation. The blurred image was restored to ensure recognition accuracy over 3m working distance with 400mm focal length and aperture F/6.3 optics. The simulation result as well as experiment validates the proposed code apertured imaging system, where the imaging volume was 2.57 times extended over the traditional optics, while keeping sufficient recognition accuracy.

Type II InAs/GaSb superlattice material, because of its excellent predominance, is becoming the best choice for the third generation infrared detector. Surface passivation, which is one of the most important process during the device fabricated, can improve the performance of superlattice detector greatly. In this work, three passivation methods were experimented based on MWIR superlattices, then after electrodes were fabricated, detectors were tested. From the measurements, the passivation of anodic sulfide cooperating with SiO₂ is more effective than others, zero-bias resistance area product of device with 5μm cutoff wavelength reach up to 10⁴Ω•cm² at 77K, reverse-bias dark current density is reduced to 10^-5A/cm² at -1V, peak detectivity is 10¹⁰cm•Hz^1/2/W and quantum efficiency reach 35%. Retest after a month later, the performance of photodiodes without diversity.

For 320x240 pixel² uncooled focal plane array detector, an infrared continuous zoom optical system of 10^x zoom ratio for long-wavelength is designed in this paper. This system can be applied in joint transform correlator and other infrared tracing systems. The spectral band of the system is 8μm~12μm, the focal length is 20mm ~200mm , and the F number of the system is 2. The relative aperture is invariant during the zoom process, and the variable magnification curve and compensation curve are smooth as well. The system only consists of 7 lenses and one aspherical surface. The results have shown that when the maximum spatial frequency is 17lp/mm, the MTF(Modulation Transfer Function) curves in the whole range of focal length are all above 0.5 which are closed to diffraction limited curve. The stability of image plane is well, and the imaging quality is perfect, which show that the system meets the requirement of technical specification.

The widely investigated signals are mainly nonstationary and nonlinear signals, thus it is difficult to get the precise information from the nonstationary and nonlinear signals. Here we introduce a new method to process the nonstationary and nonlinear signals. And this new algorithm makes a good performance on processing the nonstationary and nonlinear signals. This paper mainly describe the basic theory of the new algorithm——Hilbert-Huang Transform. The Hilbert-Huang Transform is composed of Empirical Mode Decomposition and Hilbert transform. The problems of this arithmetic are summarized, such as the end effects, stop criterion and so on, and the solutions of these problems are put forward. This paper also provides some improved methods based on the Empirical Mode Decomposition in the end, such as Adaptive Time Varying Filter Decomposition, Extremum filed Mean Mode Decomposition and Improved Extremum field Mean Mode Decomposition.

With the development of infrared technology and material, infrared zoom system is playing an important role in the field of photoelectric observation, the demand of infrared systems is increasing rapidly. In order to satisfy the requirement of infrared tracking imaging requirements of a car optoelectronic devices, different kinds of mechanical structure has been discussed, finally, according to the character of the optical design result, cam mechanism is adopted in zoom mechanism design, ball screw has been used in focusing mechanism design. As is known to all, cam is the key part in zoom system, the static, dynamic and thermal characteristics of the cam make great effect on the system performance because of the greater impact of the car’s shaking and a larger range of temperature changes, as a result, the FEM analysis is necessary. The static performance is all right obtained by the finite element analysis results, the cam’s first -order natural frequency is 97.56 Hz by modal analysis, the deformation of cam in the temperature difference of 80 °C is no more than 0. 003 mm by thermal analysis, which means the mechanical performance of the cam is fine. at last, the focusing mechanism has been designed, and analysis of focusing mechanism precision and encoder theoretical resolving power has been done, this mechanism has the advantages of simple transmission chain and low friction, as well as reducing the transmission error, an absolute encoder is chosen to detect the displacement of the focusing mechanism, the focusing precision is 5μm, the encoder theoretical resolving power is 0.015μm. In addition, the measurements on how to suppress stray radiation have been put forward. The experiment afterward showed that the infrared zoom system performs well, which provides lot of experience in infrared zoom system design and adjustment.

In this paper, we investigated the characteristic of radar target, the spherical and the pyramidal missile warheads, and compared the RCS and performance of the targets with and without the cover of the plasma metamaterials. Numerical simulation is obtained by the numerical calculation Finite-difference time-domain method (FDTD). The parameters of plasmonic structures as a metamaterial cloak was designed and optimized. The relationship between the parameters of the cloak and the corresponding electromagnetic characteristic of the target are analyzed by the simulation and discussion in broadband radar signals. After optimization, the plasma cover could attenuate 40 dBsm of the radar cross section (RCS) of the targets maximally. The result shows that the anomalous phenomenon of cloaking and stealth effects induced by plasma materials for the radar target, which might have potential application of military affairs.

During the process of laser propagation in free space, energy attenuation is brought by atmospheric medium. One of the major problems about laser propagation is that atmospheric component does not remain constant within the whole altitude band. So working out the relatively accurate attenuation coefficient is a research interest of many researches for several years. On this basis of analysis of the atmospheric component distributing characteristic, simple and practical simulate approach was given to meet the needs of laser rangefinder. The main work is the research on 1.06μm YAG laser transmission characteristics in the atmosphere, and the atmosphere loss of the mathematical model is investigated. The paper discussed the influence of atmospheric attenuation on ranging ability of laser rangefinder and analyzed the atmospheric attenuation theoretical. It showed that when the attenuation coefficient γ increases the detectable distance decreases rapidly. In the condition of three transmission modes, which are ground-to-ground mode, ground-to-air mode and air-to-air mode, the relationships between atmospheric transmittance and different visibility, different zenith angle were analyzed. Minimal detectable power of laser rangefinder represents ranging ability in above-mentioned three different modes was formulated with atmospheric transmittance. Based on the results, we can adjust the experimental parameters and achieve more desirable results. It has positive influence for the design of laser rangefinder.

Signal CCD/CMOS sensors capture image information by covering the sensor surface with a color filter array(CFA). For each pixel, only one of three primary colors(red, green and blue) can pass through the color filter array(CFA). The other two missing color components are estimated by the values of the surrounding pixels. In Bayer array, the green components are half of the total pixels, but both red pixel and blue pixel components are quarter, so green components contain more information, which can be reference to color interpolation of red components and blue components. Based on this principle, in this paper, a simple and effective color interpolation algorithm based on green components and signal correlation for Bayer pattern images was proposed. The first step is to interpolate R, G and B components using the method-bilinear interpolation. The second step is to revise the results of bilinear interpolation by adding some green components on the results of bilinear interpolation. The calculation of the values to be added should consider the influence of correlation between the three channels. There are two major contributions in the paper. The first one is to demosaick G component more precisely. The second one is the spectral-spatial correlations between the three color channels is taken into consideration. At last, through MATLAB simulation experiments, experimental pictures and quantitative data for performance evaluation-Peak Signal to Noise Ratio(PSNR) were gotten. The results of simulation experiments show, compared with other color interpolation algorithms, the proposed algorithm performs well in both visual perception and PSNR measurement. And the proposed algorithm does not increase the complexity of calculation but ensures the real-time of system. Theory and experiments show the method is reasonable and has important engineering significance.

This paper presents a low power and small area analog-digital converter (ADC) for infrared focal plane arrays (IRFPA) readout integrated circuit (ROIC). Successive approximation register (SAR) ADC architecture is used in this IRFPA readout integrated circuit. Each column of the IRFPA shares one SAR ADC. The most important part is the three-level DAC. Compared to the previous design, this three-level DAC needs smaller area, has lower power, and more suitable for IRFPA ROIC. In this DAC, its most significant bit (MSB) sub-DAC uses charge scaling, while the least significant bit (LSB) sub-DAC uses voltage scaling. Where the MSB sub-DAC consists of a four-bit charge scaling DAC and a five-bit sub-charge scaling DAC. We need to put a scaling capacitor Cs between these two sub-DACs. Because of the small area, we have more design methods to make the ADC has a symmetrical structure and has higher accuracy. The ADC also needs a high resolution comparator. In this design the comparator uses three-stage operational amplifier structure to have a 77dB differential gain. As the IR focal plane readout circuit signal is stepped DC signal, the circuit design time without adding the sample and hold circuit, so we can use a DC signal instead of infrared focal plane readout circuit output analog signals to be simulated. The simulation result shows that the resolution of the ADC is 12 bit.

Degree of polarization (DOP) is an important physical quantity for describing the optical polarization effect and is widely applied in optical fiber communication, optical fiber gyro and the related technologies. Currently, the optical polarization degree tester for the purpose of communication uses mainly two kinds of measurement methods: Stokes vector method and extremum method. At present, there isn’t a standard to measure the accuracy and consistency of DOP parameter measurement by the devices listed above, affecting seriously the application of DOP parameter measurement in the fields of optical fiber gyro and optical fiber communication. So, it is urgent to table the accurate guarantees to trace the source of quantitative values of the DOP measuring devices and testers. In this paper, the polarization beam combination method is raised to research and manufacture the standard optical fiber light source device with the variable DOP, and an indicated error measurement has been conducted for a DOP meter. A kind of standard optical fiber light source device that uses a single light source to realize the variable DOP is put forward. It is used to provide the accurate and variable optical fiber polarization degree light with a scope of 0～100%. It is used to calibrate the DOP meters and widely applied in the field of national defense and optical communication fields. By using the standard optical power meter, DOP value by which the optical power meter calculates the optical signal can be measured, which will be used ultimately for calibration of the DOP meter. A measurement uncertainty of 0.5% is obtained using the polarization beam combination method.

Volcano eruption can produce a mass of volcanic ash floating in the air for a long period, which will seriously threaten the aerial planes safety, and cause the air pollution, it could do harm to people’s living environment and their health. Take the Iceland Eyjafjallajokull volcano as an example which erupted in April to May 2010, the volcano ash cloud were derived with the visible and infrared scanning radiometer of FengYun-3(FY-3 VIRR) meteorological satellite data. The medium wave infrared (MWIR) and the thermal infrared split windows (THIR-SW) data were used separately. the MODIS THIR-SW data were also be used to retrieve ash cloud to test the results derived from FY-3 VIRR data. It showed that the MWIR was more applicable for the ash cloud retrieving than the THIR-SW with FY-3 VIRR data, and the threshold value should be adjusted to around negative 1 rather than 0 for VIRR THIR-SW data. And the threshold should be adjusted with the THIR-SW of FY-3. The ash cloud radiation and bright temperature(BT), spatial distribution characteristics were also analyzed quantitatively with the two channels data. The study could provide parameters for the prediction of volcanic ash cloud dispersion simulate. When the real temperature of lava flow were high enough, the sensor will show a false bright temperature, how to retrieve the real temperature of the higher lava flow is a problem need to be studied in the future.

In order to improve the definition of the infrared image, and make it more accessible for human eyes, an infrared image enhancement algorithm based on Riemann-Liouville (R-L) fractional calculus and human visual properties is proposed in this paper. Combining the mathematical model of human retinal receptive field with R-L fractional calculus theory, an R-L fractional order Rodieck enhancement mask is designed. The mask is used to enhance the textures and edges of the image. Then, the grayscales of the enhancement result are adjusted according to the grayscale resolution capabilities of human eyes. It further improves the contrast of infrared images. Experimental results show that the proposed algorithm can effectively enhance the texture details and contrast of infrared images. Compared with histogram equalization method and multi-Retinex method, the enhancement result of the proposed algorithm has better visual effect, and it is more accessible for human eyes.

Target detection, segmentation and recognition is a hot research topic in the field of image processing and pattern recognition nowadays, among which salient area or object detection is one of core technologies of precision guided weapon. Many theories have been raised in this paper; we detect salient objects in a series of input infrared images by using the classical feature integration theory and Itti’s visual attention system. In order to find the salient object in an image accurately, we present a new method to solve the edge blur problem by calculating and using the edge mask. We also greatly improve the computing speed by improving the center-surround differences method. Unlike the traditional algorithm, we calculate the center-surround differences through rows and columns separately. Experimental results show that our method is effective in detecting salient object accurately and rapidly.

In order to improve the efficiency of processing the large amount of data of infrared image, in this paper we develop a new infrared image processing method based on compressed sensing (CS) and simulate the method. The basic idea behind CS is that a signal or image, unknown but supposed to be compressible by a known transform, (eg. wavelet), can be subjected to fewer measurements than the nominal number of pixels, and yet be accurately reconstructed. According to the properties of wavelet transform sub-bands, firstly we make wavelet transform which change the infrared image into a wavelet coefficients matrix. Acquired the features of infrared image, the characters of the wavelet coefficients can be concluded. When deeply analyzing the data of the wavelet coefficient, we can easily find the high-pass wavelet coefficients of the image are sparse enough to measure, while the low-pass wavelet coefficients are not appropriate for measure. So in this second part, only measured the high-pass wavelet coefficients of the image but preserving the low-pass wavelet coefficients. For the reconstruction, the third part, by using the orthogonal matching pursuit (OMP) algorithm, high-pass wavelet coefficients could be recovered by the measurements. Finally the image could be reconstructed by the inverse wavelet transform. The simulation proves that applying the CS theory to the realm of infrared picture can decrease the amount of data which must be collected. Besides, compared with the original compressed sensing algorithm, simulation results demonstrated that the proposed algorithm improved the quality of the recovered image significantly.

A new style calibration mechanism is designed for the infrared camera working in space. This calibration mechanism adds a locking device, which will produce magnetic force to fix the moving parts on the stage of launch. It has not been taken into account in past calibration mechanism of space infrared camera. In order to simplify structure and control system, an alnico is adopted in locking device as the source of magnetic field, which interacts with magnetic material and produces locking force. In addition, there is also a special structural design, which makes magnetic circuit closeitself to control magnetic leakage interfering with other equipment. Besides, another important component of calibration mechanism is a permanent magnet torquer. It can provide driving force for the blackbody to complete two state conversions of calibration and Non-calibration. High magnetic induction intensity and coercivity alnico is used as the stator, which will lighten the weight of torquer. On-off control strategy is selected in order to simplify the control system. Because calibration is only a temporary state, temperature rise has little influence on torquer. This setup is favorable to increase its reliability. There are guard plates on the axial direction shielding electromagnetism, also reducing magnetic leakage. Experimental investigations have been carried out to verify the feasibility and reliability of design. Result indicates the calibration mechanism can primely complete the calibration task of the space infrared detector. It has an important application value on the field of infrared detection.

The high-speed and small-volume mid-wave IR zoom lens capable of 16× magnification using a 320×256 IR FPA detector has been described. The system magnification can be continuously adjusted by simply moving two lens groups, which uses the root-exchange theory. The object-image exchange theory and root-exchange theory are presented. The structure using root-exchange theory can get large zoom ratio with simple volume and the smooth zoom curve. Mechanically compensated IR zoom lens design has these questions: firstly, big volume caused by complex optical structure; secondly, limited IR material and obvious focus shift with temperature change. The zoom lens using mechanically compensated method has solved all the questions that existed in traditional system. The system also contains much less optical material and has a very simple structure by using DOE elements. The element of first moving group and the second element of the second moving group are both DOE. As the DOE has minus Abb number, which is opposite of refractive materials, it can minimize the higher order chromatic aberration. Based on the characteristics, the chromatic aberration was balanced. Research on the thermal analysis and compensation is considered. The passive athermalization is made by DOE elements. DOE elements make the zoom lens maintain its performance when it is operating between -20°C and 60°C.The results show the high magnification zoom lens design performance, with small volume and light weight. The aberration of the system were well corrected and diffraction limited performance was achieved in required temperature range.

Optical activity is the intrinsic property of chiral molecules. Investigation of optical activity is particularly important for diagnosing and monitoring blood glucose of diabetes. The experimental setup to obtain the Mueller matrix in the forward detection geometry is used. Three kinds of chiral turbid media are selected to be studied in the experiment. The first is the tissue phantom composed of an aqueous solution of glucose mixed with PST sphere suspensions. The second is the actual chicken blood mixed with glucose solution. The last is the vein blood plasma of diabetic patients. The results presented in this study demonstrate that the method of Mueller matrix decomposition can be used to quantitatively extract the optical rotation of chiral molecule in turbid medium. The rotation angle has linear relationship with the concentration of the optical activity material when the scattering coefficient of the turbid medium maintains unchanged. The scattering effect enlarges the rotation angle. Furthermore, optical rotation abides by the Drude’s dispersion equation. The decomposition method also has been found useful applications in quantifying the optical rotations due to blood glucose in diabetic patients. The diabetic severity status can be distinguished with the rotation angle of glucose by using the decomposition method and also are in accordance with the clinical diagnosis. Thus, the method of Mueller matrix decomposition has promising applications in diabetic diagnosis.

In this paper we reported our systematic studies on InSb interface growth in InAs/GaSb SLs structure. Two typical interfaces growth mode, migration-enhanced epitaxy (MEE) and conventional molecular beam epitaxy (MBE), were designed for the 12 ML InAs/12 ML GaSb SLs material and the detail properties were discussion by the experimental measurement and simulation analysis. Our results indicated that the surface of SLs sample with the InSb interface layers grown by MEE method shows smaller RMS both on the 2 μm x 2 μm and 50 μm x 50 μm scan area by AFM measurement, and its PL intensity is about 1.3 times stronger than that of SLs sample grown by MBE. Besides, the MEE samples had significant As composition in InSb interface layers which was extracted by the HRXRD fitting.

In this paper, we present a novel iterative interpolation super-resolution algorithm based on the edge-directed interpolation algorithm (NEDI) and the iterative-interpolation super-resolution algorithm (IISR). Our proposed algorithm introduces the NEDI which has only been used for single-image interpolation in previous researches into multi-frame interpolation area of the IISR by way of mapping two images with a 0.5 pixel shift along both directions into a high-resolution grid and populating the grid using improved NEDI. The novel algorithm employs an iterative interpolation process which can be divided into two steps. Firstly, we map low resolution images into the high resolution grid, and use the new interpolation method based on improved NEDI to interpolate the grid to create the first approximation image. Secondly, to satisfy the observation constraints provided by the given low-resolution images, we implement the iteration procedure during which the error vector between the simulated low resolution image and the original one is reconstructed into a high-resolution error image using the same interpolation technique as the first approximation image. After several iteration cycles, the reconstructed high resolution image converging to the real scene is achieved. Absorbing the merits of NEDI and the iterative procedure as well as the improvement to them, the proposed algorithm can preserve the edges well and achieve higher reconstruction accuracy without amplifying the noise and with very few artifacts though using insufficient low resolution images. At last, we carry out a simulation experiment with grayscale images and color images, and the new algorithm demonstrates much better performance compared with some previous normal methods, and the application to noise corrupted low resolution images confirms its robustness.

A new hollow nanoshell semiconductor was applied for generating smoke screen, and the dispersion and infrared jamming performance were researched. Firstly, the mircostructures and dispersion performance of the screen particles were analized by using SEM and cascade impactor; basing on the findings, the jamming performance of the screen to 8-12μm infrared light, 1.06 μm laser and 10.6 μm laser were examined, and the primary affecting factors and relationships got concluded. The results show that the dispersion performance is favorable as the diameters of more than 70% smoke particles are below 6.1μm; the smoke screen has better and satisfactory jamming performance to IR and laser as within 10 min, the decay rate maintains above 85% to 8-12μm IR and 90% to 1.06μm laser and10.6μm laser.

This paper mainly studies how to detect a wide variety of ships from the ship-borne infrared images in order to implement sea monitoring. Different types of ships have significant differences in their appearance. The traditional detection method which uses the global texture features of the object is not suitable to detect varied ships. This paper presents a novel detection algorithm which extracts spatial partial texture features trained by Adaboost to establish the ship model for detection. We first extract all the partial regions of the object through random traversal, and then extract the texture features by using the “Uniform LBP” operator. Compared to the traditional way, we save each partial feature individually as one feature vector, which not only reduces the vector dimension but also highlights the key regions when the partial regions with strong generality are selected by Adaboost at the second step. Finally, the selected partial features are boosted with weights to establish ship model for the ship detection. The proposed approach is efficient and robust in the infrared ship detection.

Many investigations show that almost all detection systems operating in visible light and infrared wave bands are subject to severe performance degradation when they are used in fog. It is necessary to study the influence of fog on the photoelectric sensors so as to find out applicable countermeasures. However, it is hard to get enough meaningful data tested in nature fog. If the forming of fog can be controlled artificially, more credible research methods and experiment conditions will be acquired for studying the electromagnetic wave transmission in fog. In this paper, artificial fog was produced with the fog aerosol specially prepared with oxidant, fuel and bond. Through combustion reaction, the fog aerosol could generate artificial condensation nucleuses, which were provided with fog catalyzing capabilities and able to condense water vapor in air and produce artificial fog within several minutes. Three types of fog aerosols of different oxidant (code-named as NP/KP/LP) were prepared for the experiments. And the influence of oxidant on the photoelectric obscurity performance and the microphysical characteristics of artificial fog were researched. The photoelectric obscurity performance was tested by an IR imaging sensor and an illuminometer sensor, and the microphysical characteristics were tested by the laser granularity system. The experiment results showed that the artificial fog had good photoelectric obscurity and aerosol LP had the best. The attenuation of visible light and infrared wave band (3～5μm) in the fog were above 90%; and the attenuation of infrared wave band (8～14μm) was above 80%. Moreover, the oxidant affected closely the microphysical features of the condensation nucleus, such as the size distribution and number density. It is noticeable that while the size distributions of droplets presented similar trajectories even with different fog aerosols, the coagulation and growth rates of droplets were controlled by the fog catalyzing capabilities of condensation nucleus. Obviously, the maximal droplet concentration and the highest droplet growth rate were obtained form aerosol LP, from which, therefore, the fog catalyzing capability was the best. In conclusion, the oxidant of the fog aerosol greatly affects the catalyzing capabilities of nucleuses and the droplets growth processes, and consequently leads to the difference of photoelectric obscurities.

Following with the “high-resolution upsurge” appeared in many counties in recent few years, it is an inevitable trend to increase the size of the Optical Telescope. However, because of the volume constrains of space-borne astronomical instruments, segmented reflector is thought as the main measure of future astro-physical missions by many scientists. In this paper, a coaxial three-mirror anastigmatic system (TMA) with a segmented primary mirror is modeled in optical software. The optical system, which has 2.4m aperture, 48m focal length and the field-view angle of 0.3°×0.06°, works in the 450nm~900nm wave band. The ‘1+6’ aperture-stiching model is applied. Firstly, the initial structure of the system is inputted to the CODEV, and a certain constraint functions are set, and then the system automatically optimizes. Finally, designing results show that the Modulation Transfer Function (MTF) is really very near to the limit of diffraction. We get a good image quality of the optical system design results.

During the large visual angle IR image distortion rectification process there are some difficulties, first pick-up rectifying points is hard, second measuring and rectifying distortion are wasting time, third rectifying screen is difficult to make and it costs much. In order to overcome those disadvantages an IR imaging distortion rectification method, which using asterisk rectifying screen, is proposed. This method takes the image of a special made asterisk rectifying screen at first, then using SIFT operator to detect the real imaging positions of rectifying points in the image. Based on the real positions mean slope is used to compute theoretical imaging positions of those rectifying points. After that least square arithmetic is adopted to calculate the distortion parameters. The experiment result has shown that: the proposed method has the advantages of high precision, low cost, simple process and universal applicability.

Using super-resolution (SR) technology is a good approach to obtain high-resolution infrared image. However, Image super-resolution reconstruction is essentially an ill-posed problem, it is important to design an effective regularization term (image prior). Gaussian prior is widely used in the regularization term, but the reconstructed SR image becomes over-smoothness. Here, a novel regularization term called non-local means (NLM) term is derived based on the assumption that the natural image content is likely to repeat itself within some neighborhood. In the proposed framework, the estimated high image is obtained by minimizing a cost function. The iteration method is applied to solve the optimum problem. With the progress of iteration, the regularization term is adaptively updated. The proposed algorithm has been tested in several experiments. The experimental results show that the proposed approach is robust and can reconstruct higher quality images both in quantitative term and perceptual effect.

The InGaAs focal plane array (FPA) detectors, covering the near-infrared 1~2.4 μm wavelength range, have been developed for application in space-based spectroscopy of the Earth atmosphere. This paper shows an all-metal vacuum package design for area array InGaAs detector of 1024×64 pixels, and its architecture will be given. Four-stage thermoelectric cooler (TEC) is used to cool down the FPA chip. To acquire high heat dissipation for TEC’s Joule-heat, tungsten copper (CuW80) and kovar (4J29) is used as motherboard and cavity material respectively which joined by brazing. The heat loss including conduction, convection and radiation is analyzed. Finite element model is established to analyze the temperature uniformity of the chip substrate which is made of aluminum nitride (AlN). The performance of The TEC with and without heat load in vacuum condition is tested. The results show that the heat load has little influence to current-voltage relationship of TEC. The temperature difference (ΔT) increases as the input current increases. A linear relationship exists between heat load and ΔT of the TEC. Theoretical analysis and calculation show that the heat loss of radiation and conduction is about 187 mW and 82 mW respectively. Considering the Joule-heat of readout circuit and the heat loss of radiation and conduction, the FPA for a 220 K operation at room temperature can be achieved. As the thickness of AlN chip substrate is thicker than 1 millimeter, the temperature difference can be less than 0.3 K.

Influenced by detectors’ material, related manufacturing technology etc, every detection element’s responsivity in infrared focal plane arrays(IRFPA) is different, which results in non-uniformity of IRFPA. So non-uniformity correction(NUC) is an important technique for IRFPA. The classical two-point NUC algorithm based on reference sources is analyzed in this paper. And a new NUC algorithm based on statistical characteristics of image serial is presented. In this algorithm, the reference images are constructed from image serial, and correction parameters are computed by using the constructed reference images. Then two-point NUC is applied to output images of IRFPA. Experimental results show that the algorithm proposed in this paper is effective and implemented easily.

After a decoy is released, it can fly around the target aircraft in a short period of time. And it can radiate infrared spectral radiation similarly to the target do. So it is difficult to recognize the target aircraft. But in infrared images, decoys and targets have different geometrical features. So an infrared decoys recognition method based on the geometrical features is proposed in this paper. The geometrical features of the candidates in each image are extracted, such as the major axis, the minor axis, the aspect ratio, area etc. Then the differences on these geometrical features can be used to recognize targets and decoys. A simulation was done on a set of images that contain decoys and targets by using this method. The results show that the algorithm proposed in this paper can better distinguish infrared decoys and targets.

Muzzle smoke produced by weapons shooting has important influence on infrared (IR) system while detecting targets. Based on the theoretical model of detecting spot targets and surface targets of IR system while there is muzzle smoke, the function range for detecting spot targets and surface targets are deduced separately according to the definition of noise equivalent temperature difference(NETD) and minimum resolution temperature difference(MRTD). Also parameters of muzzle smoke affecting function range of IR system are analyzed. Base on measured data of muzzle smoke for single shot, the function range of an IR system for detecting typical targets are calculated separately while there is muzzle smoke and there is no muzzle smoke at 8～12 micron waveband. For our IR system function range has reduced by over 10% for detecting tank if muzzle smoke exists. The results will provide evidence for evaluating the influence of muzzle smoke on IR system and will help researchers to improve ammo craftwork.

Focal-plane-array (FPA) chips are the most significant components in imaging systems. Complicated measurements are performed to test chips’ properties, including resolution, signal-to-noise ratio, frame rate and homogeneity. Regular test systems are usually composed of bulky and complicated instruments, which take up large space and can only be used in labs. Besides, some indispensable parts such as high-precision signal generator and high-speed data acquisition module are very expensive, resulting in a high cost of the whole system. In order to test ultraviolet and infrared FPA chips, especially in some particular environments, such as radiation exposure tests, we designed and fabricated a flexible and portable test system for FPA chips. On the basis of Field-Programmable-Gate-Array (FPGA) technology, we integrated the system into one circuit board, which is portable and convenient for out-lab circumstances. Compared to the traditional test systems, the developed system costs much lower with a reasonable accuracy sacrifice. Several ultraviolet FPA chips have been tested on the developed system. Generated signals are monitored with digital oscilloscope, and the experimental results show that the system works well and meets the design requirements.

The authors report the study of thermal annealing (TA) effects on the intersubband transitions (ISB-T) properties in (CdS/ZnSe)/BeTe and CdS/ZnSe multiple quantum wells (MQWs). The samples were grown on (001)-GaAs substrates by molecular beam epitaxy. With the increase of annealing temperature, the ISB-T shifts to longer wavelength in (CdS/ZnSe)/BeTe MQWs, but to short wavelength in CdS/ZnSe MQWs. The ISB absorption vanishes at the annealing temperature of 270 °C for CdS/ZnSe QWs while survives to up to 440 °C for (CdS/ZnSe)/BeTe QWs. For (CdS/ZnSe)/BeTe MQWs after 20 minutes of TA, absorption wavelength and intensity become stable. For CdS/ZnSe MQWs, however we observed a blue shift in wavelength accompanied by a decrease of intensity after 45 minutes of TA. Photo-induced ISB-T measurements indicate that the disappearance of ISB absorption results from the loss of free-carriers in the well layers. ω/2θ scan and two-dimensional reciprocal space mapping (2DRSM)) measurements of X-ray diffraction (XRD) indicate that a built-up of tensile strain and interdiffusion at interfacial region in the annealed (CdS/ZnSe)/BeTe heterostructrues. 2DRSM also shows the enhanced structural relaxation in CdS/ZnSe MQWs. Based on the XRD analysis, the effects of TA on the ISB-T in (CdS/ZnSe)/BeTe and CdS/ZnSe MQWs are explained.

Electrochemical Capacitance-Voltage (EC-V) profiling is currently one of the most often used methods for majority carrier concentration depth profiling of semiconductors. The experiments of EC-V profiling on InP based structures were conducted by Wafer Profiler CVP21, and there are two problems in the experiments of InP based p-i-n structures : a）the experimental results of EC-V profiling of i layer were not in line with the theoretically data after the EC-V profiling of p layer, which can be measured within the error range; b) The measurements of etching depth were not very accurate. In this paper, we made comparative experiments on InP based n-i-n structures, and find out a method to deal with the first problem: firstly etch p layer before EC-V profiling, so we can gain a relatively accurate result of EC-V profiling of i layer. Besides, use back contacts instead of front contacts to do the EC-V profiling according to the instruction book of the Wafer Profiler CVP21. Then the author tried to infer the reason that results in the first problem theoretically. Meanwhile we can calibrate the etching depth through Profile-system and Scanning Probe Microscope (SPM). And there are two possible reasons which result in the second problem: the defects of the semiconductors and the electrolyte we used to etch the semiconductors.

This paper proposes a multiscale deployment of Compressed Sensing(CS) in a new transform domain for image reconstruction. The new transform, directly built in the discrete framework, combines the traditional discrete wavelet transform with shearing filter banks defined in the Pseudo-Polar frequency domain to perform multiresolution and multidirectional analysis of images. Then a specific decimation way is applied to further get rid of extra redundancy with no aliasing. The proposed transform named wavelet-based discrete shearlet transform (WBDST) which can be seen as a extension of the original discrete shearlet transform is also optimally efficient in representing images containing edges while offering a dramatically low redundant property. Furthermore, we deploy a multiscale CS scheme in WBDST domain for image reconstruction, different scales are segregated and CS is applied separately to each one. Numerical experiments demonstrate that this deployment gives much better quality reconstructions than those of the WBDST based best N-term approximation as well as the curvelets based multiscale CS scheme.

Infrared photodetectors were widely applied in satellite detection, infrared-guided, infrared early warning and infrared imaging and so on. Currently, InAs/GaSb type-II superlattices (T2SLs) photodetectors have been attracted by their unique band-structure and potential applications. In this paper, the InAs/GaSb T2SLs photodetectors in mid-wavelength infrared (MWIR) spectral range were fabricated with p-i-n structure, and the process parameters were optimized. The multilayer structure was grown on GaSb substrate by Molecular Beam Epitaxy (MBE). The active area of this photodetector was 260μm×260μm, and the sidewall of mesa was protected by SiO₂ layer. The thickness of adsorption layer was 1060 nm. To reserve more incident area and to avoid the damage caused by welding process, the pad of electrodes were designed under the mesa. A annular electrode was designed to shorten the transmission time of carriers to improve the collection efficiently. The cut-off wavelength λ_c of the detector was 4.2μm@77K, and the dark current density was measured as 1.07×10^-3 A/cm²@V_b=-0.1V. The peak of specific blackbody detectivity (D*) was equal to 1.05×10¹⁰ cmHz^1/2/W at zero-bias.

ZnS thin films were prepared on HgCdTe substrates by thermal evaporation and megnetron sputtering deposition technique. The morphology, structure, composition, and optical properties of two kinds of ZnS thin films were studied by scanning electron microscope(SEM), X-ray diffraction(XRD), energy dispersive X-ray analysis(EDX) and fourier transform infrared(FTIR) spectrometer. Then the HgCdTe MIS devices using ZnS thin film as insulating layer were successfully fabricated. The C-V measurement of MIS devices was used to study electrical characteristics of the ZnS/HgCdTe interface. The experimental results show that, the ZnS thin films by thermal evaporation and megnetron sputtering both have good transmission characteristics in infrared waveband and close atomic ratios of Zn/S. The former one exhibits zincblende structure and a phenomenon of layer growth, but the latter one exhibits wurtzite structure and an obvious phenomenon of island growth. It is also found that, the former one has less fixed charge density than the latter one.

This text makes use of the similar of the principle between IR imaging guided missile detection system and the general sight optics probe. In this text, the synopsis analysis on the jamming effectiveness of the IR smoke projectile resist the IR imaging guided missile is discussed. This research of the jamming technique to IR imaging guided missile have a very realistic meaning.

A single-photon detecting array of readout integrated circuit (ROIC) capable of infrared 3D imaging by photon detection and time-of-flight measurement is presented in this paper. The InGaAs avalanche photon diodes (APD) dynamic biased under Geiger operation mode by gate controlled active quenching circuit (AQC) are used here. The time-of-flight is accurately measured by a high accurate time-to-digital converter (TDC) integrated in the ROIC. For 3D imaging, frame rate controlling technique is utilized to the pixel's detection, so that the APD related to each pixel should be controlled by individual AQC to sense and quench the avalanche current, providing a digital CMOS-compatible voltage pulse. After each first sense, the detector is reset to wait for next frame operation. We employ counters of a two-segmental coarse-fine architecture, where the coarse conversion is achieved by a 10-bit pseudo-random linear feedback shift register (LFSR) in each pixel and a 3-bit fine conversion is realized by a ring delay line shared by all pixels. The reference clock driving the LFSR counter can be generated within the ring delay line Oscillator or provided by an external clock source. The circuit is designed and implemented by CSMC 0.5μm standard CMOS technology and the total chip area is around 2mm×2mm for 8×8 format ROIC with 150μm pixel pitch. The simulation results indicate that the relative time resolution of the proposed ROIC can achieve less than 1ns, and the preliminary test results show that the circuit function is correct.

For the dual band IR imaging system to track targets in the air, due to the uniform sky background, it is difficult to extract salient features besides the tracked targets. But in the dual band IR image sequence, the target in the air has the same trajectory. So the trajectory can be used as feature to register dual-band IR images. If the target trajectory is uniform, the accuracy of double wave band image registration method based on moving targets’ track will be greatly reduced. In addition to detect the target trajectory, it is necessary to detect other feature points in the background, such as the corners. Therefore, in this paper we first detect the target trajectory in the middle-wave infrared image sequence and long-wave infrared image sequence. Then combined the corners in dual band images, dual-band images are registered. Experimental results shows the effectiveness of this method.

Modulation transfer function (MTF) is one of the most important parameters of infrared focal plane array (IRFPA). A double-knife edge scanning method is proposed for MTF measurement of IRFPA. In this method, a double-knife edge was used as a target, and the IRFPA under test was positioned in the focal plane of the imaging optical system by a 3-axis translation stage. With an IRFPA data acquisition system, the image of the double-knife edge was restored. By scanning in the direction orthogonal to the double-knife edge image, edge spread function (ESF) curve of each pixel swept across the knife-edge image was obtained. MTF could be calculated from the subsequent fitting, differential and Fourier transformation procedures. With double-knife edge scanning, two ESF curves of double-knife edge were obtained simultaneously, and symmetry of the two ESF curves could be used to evaluate the verticality between photosensitive surface of IRFPA and optical axis of the double-knife edge imaging system. In addition, this method can be used to judge the existing of interference from outside such as vibration, stray light and electrical noise. A measurement facility for IRFPA’s MTF based on double-knife edge scanning method was also established in this study. The facility is composed of double-knife edge imaging optical system, 3-axis translation stage and data acquisition system, et al. As the kernel of the facility, the double-knife edge imaging optical system mainly comprises two symmetrical parabolic mirrors coating with reflective material, and the magnification of the optical system is 1 with an operation wavelength range of (1∼14) μm.

With the advantages of stealthiness, all weather effectiveness, visible target recognition and long affect distance, infrared thermal imaging system play important role in scouting, aiming and tracking. In order to eliminate influences of thermal camouflage to traditional intensity infrared thermal imaging system, we proposed design method of ARM based infrared camouflage target recognition system. Considering the measurement of Stokes parameters, we analyzed design method of polarized image acquisition module, designed ARM core board and its data connection with other devices, adopted LCD to display polarization image computed out by ARM. We also studied embedded Linux platform and polarized image processing program based on this platform, finally actualized the design method of ARM based infrared camouflage target recognition system. Results of our experiment show that data stream can be successfully transmitted between modules of the system and the platform we used is fast enough to run polarized image processing program. It’s an effective method of using ARM to actualize infrared camouflage target recognition system.

Time of flight laser range finding, deep space communications and scanning video imaging are three applications requiring very low noise optical receivers to achieve detection of fast and weak optical signal. HgCdTe electrons initiated avalanche photodiodes (e-APDs) in linear multiplication mode is the detector of choice thanks to its high quantum efficiency, high gain at low bias, high bandwidth and low noise factor. In this project, a readout integrated circuit of hybrid e-APD focal plane array (FPA) with 100um pitch for 3D-LADAR was designed for gated optical receiver. The ROIC works at 77K, including unit cell circuit, column-level circuit, timing control, bias circuit and output driver. The unit cell circuit is a key component, which consists of preamplifier, correlated double Sampling (CDS), bias circuit and timing control module. Specially, the preamplifier used the capacitor feedback transimpedance amplifier (CTIA) structure which has two capacitors to offer switchable capacitance for passive/active dual mode imaging. The main circuit of column-level circuit is a precision Multiply-by-Two circuit which is implemented by switched-capacitor circuit. Switched-capacitor circuit is quite suitable for the signal processing of readout integrated circuit (ROIC) due to the working characteristics. The output driver uses a simply unity-gain buffer. Because the signal is amplified in column-level circuit, the amplifier in unity-gain buffer uses a rail-rail amplifier. In active imaging mode, the integration time is 80ns. Integrating current from 200nA to 4uA, this circuit shows the nonlinearity is less than 1%. In passive imaging mode, the integration time is 150ns. Integrating current from 1nA to 20nA shows the nonlinearity less than 1%.

Thermal cycling reliability is one of the most important issues whether the HgCdTe infrared focal plane array detectors can be applied to both military and civil fields. In this paper, a 3D finite element model for indirect hybrid HgCdTe infrared detectors is established. The thermal stress distribution and thermally induced warpage of the detector assembly as a function of the distance between the detector chip and Si-ROIC, the thickness and the materials properties of electrical lead board in cryogenic temperature are analyzed. The results show that all these parameters have influences on the thermal stress distribution and warpage of the detector assembly, especially the coefficient of thermal expansion(CTE) of electrical lead board. The thermal stress and warpage in the assembly can be avoided or minimized by choosing the appropriate electrical lead board. Additionally, the warpage of some indirect hybrid detectors assembly samples is measured in experiment. The experimental results are in good agreement with the simulation results, which verifies that the results are calculated by finite element method are reasonable.

This paper proposes a method to characterize a tunable liquid crystal Fabry-Perot (LC-FP) hyperspectral imaging detectors with electrically controlling and shifting wavelength of light beam penetrating the LC-FP chip proposed. Based on the effect of the directing vector distribution of LC materials can be remarkably changed and stably anchored in an electric field applied over the electrodes of the device, the refractive index of the LC materials filled into FP cavity can be modulated by voltage signal with relatively low amplitude. By the thin film matrix equation utilized, we calculated the transmissivity properties of the infrared radiation out from the LC-FP and continuously incident upon the photosensitive structure, and then acquired the basic relationship among the transmissivity, and the applied voltage signal, and the wavelength parameter selected. The key features of the proposal approach is as follows: (1) the device is mainly composed of very thin electrically modulating refractive-index architecture, which are generally two basic FP interferometers connected closely so as to accurately perform the choice of the wavelength desired in the spectral range by the interference filtering; and (2) the depths of the two FP interferometers are designed to be different, and through combination two parts mention ed above we can obtain some single wavelength desired of penetrating beam. The proposed device is being produced currently. The final device will be used to sequentially choose each desired infrared (IR) wavelength from incident IR radiation.

Laser Doppler technology is widely used in precision vibration measurement such as voice acquisition. The fundamental of voice acquisition is to detect the vibration of targets induced by sound wave using a Laser Doppler voice acquisition system, and then demodulate the voice signal from interference signal. Therefore the target’s vibration characteristics will be the principal factor influencing the effect of voice acquisition. In this paper, we focus on the plane structure’s vibration characteristics caused by voice. There are mainly two parts in this paper, simulation and experimental verify. In simulation, the finite element method is used. The Finite Element Analysis method is widely used in material properties analysis, dynamic analysis, and acoustic analysis. Through finite element analysis method, the plane structure models of thick smooth aluminum are established by ANSYS. Then the frequency responses of different constraints are compared. The Laser Doppler voice acquisition system is applied to test and verify the simulation results. The response characteristics of aluminum board under different excitation frequency are measured. The experimental results and simulation results are compared to verify the correctness and reasonableness of simulation. At the same time, this provides theoretical guidance for Laser Doppler voice acquisition system to choose targets and improve voice acquisition performance.

According to problems of the intensity imaging target detection on water surface in foggy weather such as the indistinction of the target and greatly loss of the target detail, a target detection method based on the target polarization characteristics for water surface target in foggy weather is proposed in this paper. To validate the method’s effectiveness, the indoor experiment is performed by using the simulation environment in foggy weather and the outdoor experiment is performed by using the water surface real fog environment. A lot of different intensity images and polarization images are got and then analysed and compared. The experimental results demonstrate that the polarization imaging detection can effectively obtain the polarization information of targets on water surface, and we can detect the water surface targets in foggy weather by polarization information retrieving and the target information restoring.

Measure of optical decentration plays an important role in inspection, installation and adjustment of optical system. This article describes optical measurement principle of decentration, analyzes the reason of the decentration measurement accuracy, and indicates the necessity of optimizing the optical axis. Finally, because of the error of the decentration optical axis fitting. A new method of optical axis optimization is put forward here. A mathematical model to find the best optical axis is established, which improved the optical performance of the system.

This paper presents a readout integrated circuit (ROIC) with inverter-based capacitive trans-impedance amplifier (CTIA) and pseudo-multiple sampling technique for infrared focal plane array (IRFPA). The proposed inverter-based CTIA with a coupling capacitor ^[1], executing auto-zeroing technique to cancel out the varied offset voltage from process variation, is used to substitute differential amplifier in conventional CTIA. The tunable detector bias is applied from a global external bias before exposure. This scheme not only retains stable detector bias voltage and signal injection efficiency, but also reduces the pixel area as well. Pseudo-multiple sampling technique ^[2] is adopted to reduce the temporal noise of readout circuit. The noise reduction performance is comparable to the conventional multiple sampling operation without need of longer readout time proportional to the number of samples. A CMOS image sensor chip with 55×65 pixel array has been fabricated in 0.18um CMOS technology. It achieves a 12um×12um pixel size, a frame rate of 72 fps, a power-per-pixel of 0.66uW/pixel, and a readout temporal noise of 1.06mV_rms (16 times of pseudo-multiple sampling), respectively.

A dual-channel fusion system of visual and infrared images based on color transfer The increasing availability and deployment of imaging sensors operating in multiple spectrums has led to a large research effort in image fusion, resulting in a plethora of pixel-level image fusion algorithms. However, most of these algorithms have gray or false color fusion results which are not adapt to human vision. Transfer color from a day-time reference image to get natural color fusion result is an effective way to solve this problem, but the computation cost of color transfer is expensive and can’t meet the request of real-time image processing. We developed a dual-channel infrared and visual images fusion system based on TMS320DM642 digital signal processing chip. The system is divided into image acquisition and registration unit, image fusion processing unit, system control unit and image fusion result out-put unit. The image registration of dual-channel images is realized by combining hardware and software methods in the system. False color image fusion algorithm in RGB color space is used to get R-G fused image, then the system chooses a reference image to transfer color to the fusion result. A color lookup table based on statistical properties of images is proposed to solve the complexity computation problem in color transfer. The mapping calculation between the standard lookup table and the improved color lookup table is simple and only once for a fixed scene. The real-time fusion and natural colorization of infrared and visual images are realized by this system. The experimental result shows that the color-transferred images have a natural color perception to human eyes, and can highlight the targets effectively with clear background details. Human observers with this system will be able to interpret the image better and faster, thereby improving situational awareness and reducing target detection time.

Polarization imaging provides abundant information of object, i.e. surface roughness, texture, physical and chemical characters. Independently, intensity and polarimetric features give incomplete representations of an object of interest. These representations are complementary, and it is expected that the combination of complementary information will reduce false alarms, improve confidence in target identification, and improve the quality of the scene description. Polarization parameter images include the degree of polarization, the angle of polarization, azimuth angle etc. There are not only strong correlations between polarization parameter images, but also different characters, which gives image fusion challenges, namely, how to find the optimal polarization parameter image to take part in image fusion with intensity image. This paper presents a polarization image fusion method based on choquet fuzzy integral. Using this algorithm the best polarization parameter image and intensity image are fused, and the fusion result is evaluated. The experiments show that this method could automatically select the best polarization parameter images from multi-polarization parameters image, the resulting images can yield more detail and higher contrast, and can reduce the noise effectively. It is conducive to the subsequent target detection.

Wavefront coding technique can extend the depth of filed (DOF) of the incoherent imaging system. Several rectangular separable phase masks (such as cubic type, exponential type, logarithmic type, sinusoidal type, rational type, et al) have been proposed and discussed, because they can extend the DOF up to ten times of the DOF of ordinary imaging system. But according to the research on them, researchers have pointed out that the images are damaged by the artifacts, which usually come from the non-linear phase transfer function (PTF) differences between the PTF used in the image restoration filter and the PTF related to real imaging condition. In order to alleviate the image artifacts in imaging systems with wavefront coding, an optimization model based on the PTF was proposed to make the PTF invariance with the defocus. Thereafter, an image restoration filter based on the average PTF in the designed depth of field was introduced along with the PTF-based optimization. The combination of the optimization and the image restoration proposed can alleviate the artifacts, which was confirmed by the imaging simulation of spoke target. The cubic phase mask (CPM) and exponential phase mask (EPM) were discussed as example.

Since the infrared imaging system has played a significant role in the military self-defense system and fire control system, the radiation signature of IR target becomes an important topic in IR imaging application technology. IR target signature can be applied in target identification, especially for small and dim targets, as well as the target IR thermal design. To research and analyze the targets IR signature systematically, a practical and experimental project is processed under different backgrounds and conditions. An infrared radiation acquisition system based on a MWIR cooled thermal imager and a LWIR cooled thermal imager is developed to capture the digital infrared images. Furthermore, some instruments are introduced to provide other parameters. According to the original image data and the related parameters in a certain scene, the IR signature of interested target scene can be calculated. Different background and targets are measured with this approach, and a comparison experiment analysis shall be presented in this paper as an example. This practical experiment has proved the validation of this research work, and it is useful in detection performance evaluation and further target identification research.

The problem of electromagnetic waves scattering at rough boundaries is of practical interest and has been addressed many times in different papers. Theories for investigation of rough surface scattering primarily two kinds of methods: numerical method and approximate method. As the classic analytical methods cannot calculate the electromagnetic scattering characteristics at Low Grazing Angle (LGA) accurately, in this paper, a novel method is presented by utilizing the Radar Cross Section (RCS) of the low grazing two-dimensional sea surface based on the triangles-based Physical Optics (PO) method. Firstly, the Monte Carlo method is applied to simulate the two-dimension rough sea surface in different wind speeds based on the PM sea spectrum. Then, the sea surface is generally meshed by 1/8~1/10 length of the incident wave. Secondly, the complex permittivity of the sea surface is calculated by two-Debye method and compared with the experiment. The physical optical is used to calculate the backscattering coefficient of the random rough sea surface. Considering the problem of low grazing, it is especially sampled more densely between the scattering angles 70°~90°. Then the self-shadow and inter-shadow of the sea surface at low grazing angle is taken into account, the Z-BUFFER method is used to judgment of the shadow effect. The numerical result is compared with the FEKO and good agreement is obtained. As the frequency increasing, the sea surface will have more triangles to be calculated, it will take more time. Finally, we propose a novel graphic processing unit (GPU)-accelerated decoding system. The result is 68.96 faster than its CPU counterpart.

Target signature quantitative measurement is a key problem in target signature studies. There are many factors to affect the measurement precision, especially when the target is faint. This article studies two of the most important factors, infrared imagery SNR and infrared detector fill factor. The former is related to the detector energy acquisition parameters, such as NETD, caliber, integral time, and so on. The latter is related to the detector spatial sampling feature. The conclusion of this article could give reference to infrared target quantitative measurement and infrared detector design.

For the middle wave 640×512 cooled thermal IR focal plane array with 15μm pixel pitch, a design of 3.7～4.8μm refractive infrared switchable dual-field-of-view imaging system is described, which makes use of a mechanical holder to switch two lenses into and out of the whole optical system to change the focal length from 45mm to 135mm. The system includes a telescope and a relay sub-system to avoid vignetting caused by the presence of the cold shield. Preliminary calculations are carried out first to determine the focal powers and first-order parameters of each lens and then the aberration equations are solved to achieve the initial configuration of the system as the starting point. During the optimization, in order to correct varied aberrations, such as spherical aberrations, coma, astigmatism, and chromatic aberrations, more lenses, glasses and aspherical surfaces are employed. In consideration of decreasing the manufacture cost and fabrication difficulties, only germ, silicon and one ZnS single lens are allowed to make use of, and the highest order of aspherical coefficients is no more than 8^th. Meanwhile, the separation between the two lenses fixed in the mechanical holder must be controlled strictly to make sure no ray will be obscured by them when they are switched out of the system. Between the telescope and the relay system, the relay system and the image plane, there are two mirrors to fold the system, so reserved space must be valued in the optical path. Finally, a total of ten lenses with two aspherical surfaces and two mirrors are used in the design, making the system cost effective and compact. At the end, the design results are given. The modulation transfer function (MTF) of each field-of-view is above 0.5 in all focal positions at the spatial frequency of 33lp/mm, which approaches the diffraction limits and the energy permeance ratio is greater than 80%, showing excellent performance.

An improved optical structure of a laser warning system based on microlens array is proposed aiming at the high precision imaging warning system with a smaller size. Microlens array owning the advantage of high efficiency of energy use, motion sensitivity, etc. as a multi-aperture optical element, is applied in many optical systems. It is a tough task to obtain satisfied images with a curved base microlens array because the widely used plane detectors are not fit for these kinds of microlens array with poor imaging quality though it achieves the goal of wide field of view (FOV). We address to design a model by combining the curved base microlens array with the aspheric converging lens to solve the poor imaging quality caused by cured base microlens array. This method will make it possible to enlarge the FOV with better image quality. The ray tracing results show that the image quality acquired from plane detectors is improved using curved base microlens array, but with more simple fabricated structure than that of fisheye lens, which is widely used to get a wider FOV.

To reduce the noise amplification and ripple phenomenon in the restoration result by using the traditional Richardson-Lucy deconvolution method, a novel hybrid regularization image restoration algorithm based on total variation is proposed in this paper. The key ides is that the hybrid regularization terms are employed according to the characteristics of different regions in the image itself. At the same time, the threshold between the different regularization terms is selected according to the golden section point which takes into account the human eye's visual feeling. Experimental results show that the restoration results of the proposed method are better than that of the total variation Richardson-Lucy algorithm both in PSNR and MSE, and it has the better visual effect simultaneously.

Although infrared focal plane imaging technology has been widely used in target detection and orientation, reducing pixel-pitch or increasing the number of infrared sensor array pixels was unable to meet the practical requirement for the restriction of infrared sensor’s processing technology. This paper proposes a approach that apply multi-element detector array in CS imaging system. The coded measurement technology which uses optical mask and realizes compressed sampling of target scene is described in this paper, on the basis of summarizing CS theory and algorithm. Considering the fact that the reconstruction process of large size image lasts a long time, this paper also presents a high quality image partition CS method, which requires less computing time. The simulation results point the best choice for image partition which requires the least computing time. The validity of this method also been testified using Lena gray image. Finally, according to the inconformity of recovered image via TVQC and TVEQ in pixel lever induced by image stitching, this paper presents a method to decrease the gray differences between recovered imag e blocks. Such method can effectively improve the PSNR value of recovered image, which provides a effective reference in high-resolution infrared CS imaging.

Radiometric calibration is of critical importance for information quantification of imaging polarimeters. In this paper, an integral sphere which had been traced to cryogenic radiometer was used as transfer standard in our calibration facility. The linearity, uniformity, stability of our imaging polarimeter were calibrated. The combined uncertainty in the responsivity of an imaging polarimeter was about 7.5%. At last, technical proposals of reducing uncertainty budget were briefly discussed.

Visible light imaging is one of the major means of current imaging. But the disadvantages of heavily depending on light conditions greatly limit visible light imaging. How to detect targets effectively under bad illumination conditions is a valuable research direction. Compared with the intensity imaging, the technology of polarization imaging has many advantages and extends the image information from three-dimension (light intensity, spectrum and space) to multi-dimension (the degree of polarization, angle of polarization, the polarization ellipticity and direction of rotation are added). In this paper, the method using polarization imaging technique to improve the ability of target detection and imaging quality under bad illumination conditions is proposed. Experimental results have verified the insensitivity of polarization imaging to illumination and the adaptability of polarization imaging realized the effective detection of the target and improved the target imaging quality under bad illumination conditions.

High frame rate imaging for applications such as meteorological forecast, motion target tracking require high-speed Read-Out Integrated Circuit (ROIC). In order to achieve 10 KHz of frame rate, this paper analyzes the bandwidth of Capacitive-feedback Trans-Impedance Amplifier (CTIA) in ROIC which is the dominant bandwidth-limiting node when interfaced with large InGaAs detector pixel capacitance of about 10pF. A small-signal model is presented to study the relationship between integration capacitance, detector capacitance, transconductance and CTIA bandwidth. Calculation and simulation results show explicitly how the series resistance at the interface restricts the frame rate of Focal Plane Arrays (FPA). In order to achieve low-noise performance at a high frame rate, this paper describes an optimal solution in ROIC design. A prototype ROIC chip (DL7) has been fabricated with 0.5-μm mixed signal CMOS process and interfaced with InGaAs detector arrays. Test results show that frame rate is above 10 KHz and ROIC noise is around 270 e^-, near identical to the design value.

The stereoscopic panoramic camera is a kind of important optical payload for space applications. It can image the full 360° in azimuth to the goal scene and obtain high resolution three-dimensional images. Many science investigations can be conducted by scientists with these images, such as the analysis for the planet terrain and the geology. This kind of payload has common features such as light-weight, miniaturization, and lower power consumption. This paper presents the development of a stereoscopic, panoramic imaging system for space applications, which is a typical staring binocular stereo imaging system and consists of two identical digital cameras. Each camera was build based upon a CMOS APS (Complementary Metal Oxide Semiconductor Active Pixel Sensors) and a high density FPGA (Field Programmable Gate Array). The camera has the features with the weight of about 210g and the power consumption of about 660mW. In this paper, the design details of the electronics for the specifications above are emphasized, and the designs and implements of the FPGA are particularly discussed. Finally, the verification and experiment results for the stereoscopic panoramic camera show that the design methodology is feasible.

When infrared focal plane array imaging system detects targets, especially small targets, there is the problem of low gray resolution. In this paper, an adaptive scene-based gray super-resolution technique is proposed, aiming to solve the problem. The paper gives a detailed description on the method of image gray super-resolution by adjusting the signal sample range in infrared focal plane array (IRFPA) imaging system. The method contains the following three parts: extracting the effective gray range from the scene, and obtaining the basis of super-resolution adjustment; providing the adjusting parameters after filter-predicting the basis of adjustment, combining with the adaptive LMS-based filtering algorithm; and completing gray super-resolution by controlling the parameters in super-resolution circuit. Finally, the total solution is experiment validated. The experiment in infrared focal plane array imaging system has proven the feasibility and effectiveness of this method, and the improvement of super-resolution. Then test set shows the MRTD can be increased more than one time.

The TDI-CCD Stereo Camera is the optical sensor on the Chang’E-2 (CE-2) satellite created for the Chinese Lunar Exploration Program. The camera was designed to acquire three-dimensional stereoscopic images of the lunar surface based upon three-line array photogrammetric theory. The primary objective of the camera is, (1) to obtain about 1-m pixel spatial resolution images of the preparative landing location from an ellipse orbit at an altitude of ~15km, and (2) to obtain about 7-m pixel spatial resolution global images of the Moon from a circular orbit at an altitude of ~100km. The focal plane of the camera is comprised of two TDI-CCDs. The control circuits of the camera are designed based on two SRAM-type FPGAs, XQR2V3000-4CG717. In this paper, a variable frequency control and multi-tap data readout technology for the TDI-CCD is presented, which is able to change the data processing capabilities according to the different orbit mode for the TDI-CCD stereo camera. By this way, the data rate of the camera is extremely reduced from 100Mbps to 25Mbps at high orbit mode, which is benefit to raise the reliability of the image transfer. The results of onboard flight validate that the proposed methodology is reasonable and reliable.

The existence of non-uniformities in the responsitivity of the element array is a severe problem typical to common infrared detector. These non-uniformities result in a “curtain’’ like fixed pattern noises (FPN) that appear in the image. Some random noise can be restrained by the method kind of equalization method. But the fixed pattern noise can only be removed by .non uniformity correction method. The produce of non uniformities of detector array is the combined action of infrared detector array, readout circuit, semiconductor device performance, the amplifier circuit and optical system. Conventional linear correction techniques require costly recalibration due to the drift of the detector or changes in temperature. Therefore, an adaptive non-uniformity method is needed to solve this problem. A lot factors including detectors and environment conditions variety are considered to analyze and conduct the cause of detector drift. Several experiments are designed to verify the guess. Based on the experiments, an adaptive non-uniformity correction method is put forward in this paper. The strength of this method lies in its simplicity and low computational complexity. Extensive experimental results demonstrate the disadvantage of traditional non-uniformity correct method is conquered by the proposed scheme.

This article studies the near sea surface atmosphere visibility and aerosol scattering asymmetry factor with observed weather data. Based on muti-modal log normal distribution model, Mie theory and SCE-UA method, near sea surface atmosphere aerosol parameters, such as distribution parameters and relative refractive index, are inversed. A discussion about the relationship between the inversed parameters and weather data is present.

Since infrared image quality depends on many factors such as optical performance and electrical noise of thermal imager, image quality evaluation becomes an important issue which can conduce to both image processing afterward and capability improving of thermal imager. There are two ways of infrared image quality evaluation, with or without reference image. For real-time thermal image, the method without reference image is preferred because it is difficult to get a standard image. Although there are various kinds of methods for evaluation, there is no general metric for image quality evaluation. This paper introduces a novel method to evaluate infrared image without reference image from five aspects: noise, clarity, information volume and levels, information in frequency domain and the capability of automatic target recognition. Generally, the basic image quality is obtained from the first four aspects, and the quality of target is acquired from the last aspect. The proposed method is tested on several infrared images captured by different thermal imagers. Calculate the indicators and compare with human vision results. The evaluation shows that this method successfully describes the characteristics of infrared image and the result is consistent with human vision system.

In recent years, domestic and foreign scholars have done a lot of research on the natural color image fusion technology; in which, color transfer method and the color lookup table method have been widely studied. The color transfer method needs a larger amount of calculation and the color consistency of fusion images is poorer, but the reference color images are obtained more easily. The color lookup table method is simple, real-time and can obtain better natural colors of fusion images. The image fusion method based on color lookup table and used dual-spectrum images’ gray value as the color index of fusion image, so an undesired influence on fusion image’s colors was caused by the instability of images’ gray value. A kind of improved color lookup table fusion method based on histogram matching was proposed. Firstly, mapping from dual-spectrum target images’ gray value to dual-spectrum reference images’ gray value was accomplished by utilizing histogram matching, thereby reduced the instability of gray value. Secondly, the color lookup table was complemented according to the principle that the closer the Euclidean distance is, the more similar the color is, in the range of dual-spectrum reference images’ gray scales. Finally, the fusion image was obtained from the histogram matched dual-spectrum target images by indexing the complemented color lookup table. The experimental results show that, the proposed method can effectively weaken the unexpected effect on fusion image’s colors caused by the instability of gray value and significantly improve the color fusion image’s visual effect. At the same time, the proposed method reduced portion which needs to be complemented of look-up table, so the improved method can decrease the lookup table’s data size, and increase efficiency.

Space infrared detector is the core component of photoelectric conversion in the infrared system, the indicator of which, such as sensibility and reliability, limits the optimum performance of the detection system. In the reliability research of infrared detector, the operating life of the device is a very important index and also a significant subject in the engineering application. In the accelerated life test of space infrared detector, it was difficult to periodically measure blackbody response signal of infrared detector, due to equipment limitations for a long time. Accordingly, it was also hard to get abundant failure data of devices for statistical analysis. For this problem, we designed a novel multi-station testing system for accelerated life test of space infrared device, in which response signal as well as temperature can be measured in-situ and recorded for further analysis. Based on theoretical calculation and analysis of actual measured data, we studied and designed the mechanical structure of the equipment and the key component of the testing system, such as the displacement platform, illustrated the control algorithm and put up a system design proposal which meet the testing requirements well. This work technically supports the accelerated life test of space infrared device.

Effect of γ-ray irradiations on the performance of InGaAs infrared detectors was studied. Planar-type 24×1 linear detector arrays were fabricated on n-InP/n-In_0.53Ga_0.47As/n-InP epitaxial structure by sealed-ampoule diffusion method. The InGaAs detectors were irradiated by 100krad, 300krad γ-ray at 40rad/s. The dark currents increased about 170%, 300% respectively and both decreased about 23% at the 8th hours and about 40% at the 22th hour after irradiation. Then the dark currents almost remained stable until 10 days after irradiation. Current-Voltage characteristics of the planar-type detector were analyzed. The current mechanisms were dominated by diffusion current, shunts current and generation-recombination current before irradiation. The γ irradiation resulted to increase these three current components. Ten days after irradiation, three current components all recovered partially. Capacitance-Voltage characteristics were measured before and after irradiation. Effective doping densities (N_eff) of InGaAs layer were deduced by fitting 1/C²-V curves. N_eff of detectors which were irradiated by 100krad γ-ray increased after irradiation and remained the same until 10 days after irradiation. N_eff of detectors which were irradiated by 300krad γ-ray unchanged after irradiation. The response spectrums both moved slightly towards shorter wavelength after irradiation and stayed the same until at least 10 days after irradiation.

It is an important subject in information scout, battlefield surveillance and automatic target recognition to detect interesting objects from complicated background. Compared with intensity detection, polarization detection has its advantage in identifying some camouflage targets. Usually, in the studies of target polarization detection, circular polarization property is usually neglected because of its small value. But in particular conditions, the circular polarization property of target will be used to accomplish object detection with their obviously different value. In this study, a single reflectance model of Mueller matrix is established, and based on Fresnel's law, circular polarization property of object is analyzed which is obvious while linear polarization property is obscure in particular condition. It is available to use the circular polarization component to detect target.

In this study, uniform InAs QDs were grown on the GaAs (001) substrate by MBE by the S-K mode. The effects of strain reducing layer and rapid thermal anneling on the optical properties of InAs/(In)GaAs QDs were investigated by PL measurements. The annealing results in PL peak energy red-shift which strongly depends on In composition of InxGaAs strained reducing layer , QDs with lower density and/or capped by an InGaAs layer are very sensitive to the annealing. At given annealing conditions, PL peak energy blue-shift of low-density QDs is much larger than that of high density QDs.

Along with modern infrared camouflage technique developed, it is hard to distinguish target and background by using traditional infrared intensity imaging in general because infrared feature of target and background are tending to consistent. To address this issue, a thought that utilizes infrared polarization imaging technique to detect target is proposed in this paper based on analyzing of the principle of infrared polarization imaging. The experiments are carried out for detecting of infrared low-contrast target imaging. Comparing with the infrared intensity images, the average gradient of the infrared polarization image has been improved 155% and the contrast of target and background has been improved 120% in infrared polarization images. The effective experimental data and imaging law between infrared polarization images and infrared intensity images are obtained that, the technology of infrared polarization imaging can detect details of infrared target more clearly than the infrared intensity imaging, and it can obviously increase the contrast between target and background. Therefore, it is more helpful to detecting details and features of target.

Planar 64x64 In_0.83Ga_0.17As focal plane arrays (FPA) were fabricated in this paper. The properties of In_0.83Ga_0.17As photodetectors such as I-V, responsivity, detectivity were characterized. Theoretical analysis and measurement of the dark current behavior of the detectors at 200-300K were presented. The typical bad pixels caused by excessive dark current were analyzed, the result shows that they are mainly caused by more ohmic current and trap-assisted tunneling current component. Dark current density is 0.986μA/cm² at an operating temperature of 200K and a bias voltage of -10 mV. The relative spectral response is in the range of 1.38 μm to 2.6 μm at 280K. The peak spectral response wavelength and quantum efficiency are 2.2 μm and 71.2% at 280K respectively. The achieved peak detectivity can reach 4.05x10¹¹cmHz^1/2W^-1 by thermoelectric cooling at 200K.

The scattering characteristic of complex target from terrestrial and celestial background radiation has been widely used in such engineering fields as remote sensing, feature extraction, tracking and recognition of target thus having been an attractive field for many scientists for decades. In our method, the model of target is constructed using 3DMAX and the surface is divided into triangle facets firstly. Bidirectional Reflectance Distribution Function (BRDF) is introduced and MODTRAN is applied to calculate background radiation for a given time at a given place. Finally the scattering of each facet is added up to get the scattering of the target. As the background radiance comes in all directions and in a wide spectrum and the complex target always consists of thousands of facets, in general it takes hours to complete the calculation. Consequently this limits its use in the real time applications. Recent years have seen the continual development of multi-core CPU. As a result parallel programming on multi-cores has been more and more popular. In this paper, the openMP, Intel CILK ++, Intel Threading Building Blocks (TBB) are used separately to leverage the processing power of multi-cores processors. Our experiments are conducted on a DELL desktop based on an Intel I7- 2600K CPU running at 3.40 GHz with 8 cores and 16.0 GB RAM. The Intel Composer 2013 is employed to build the program. Also in OpenMP implementation, gcc is used. The results demonstrate that highest speedups for three parallel models are 5.06X, 5.02X, 5.15X respectively.

A new arithmetic is put forward for calculating the scattering of complicated rough surface, which based on ray-tracing with BRDF. When the direction of the incident ray is fixed, the direction of the reflected ray is decided by rejection/acceptance sampling, and the standard of rejection/acceptance sampling is based on the BRDF of the surface. The reflected rays well reflect the scattering character of the complicated rough surface when there are a great lot of incident rays. Integrating the BRDF of targets into traditional ray-tracing, it could calculate the scattering of complicated surface. The test result proves the practicability of the method.

As the improvement of Astronomy technology, the size of the space optical system is developing toward huge type. However, the capability of the carriers of the space optical systems, which has got rid in the way of the development of the space optical system, is limited. To solve this problem, a self-deployable baffle is discussed, a method of the deployment utilizing elastic strain energy is advanced, and a new deployable baffle is designed in this paper. The baffle here consists of three or more sleeves, and each diameter of the sleeve is different in order to make the whole structure contract easily. The baffle is staying in contraction state until it is in the state of working. It is able to deploy into working state as required in a very short time. Well moving stabilization and high precision of deployment are ensured in this new style of deployable baffle. In order to reduce the mass of the baffle, every sleeve in the system uses the structure of thin board. As a result of the use of sleeve structure, the inner faces of the baffle are varied in each sleeve. To prove it is still effective in the optical system, professional software of ASAP is used to test its behavior. All the analysis and emulation prove that the baffle in working state is able to resist the stray light from the outside of the Field of View (FOV), improve the quality of the imaging, and meet the requirements of the optical system.

The dark current characterization of In_xGa_1-xAs with x=0.78 have been investigated. Meanwhile, the dark current related deep level trap with E_t= 0.26 eV is detected by using Deep-Level Transient Spectroscopy (DLTS). 2D simulation of dark current shows that SRH recombination, trap-assisted tunneling and band-to-band tunneling currents are the main contributors to the dark current of In_xGa_1-xAs( x=0.78) detector. To further improve the dark current characteristic, we need to improve the material growth.

The spectra have been calculated with Line by Line method for high-temperature CO₂ and atmosphere. The characteristic of the wing of atmospheric 4.3μm absorption band has been analyzed. The variation of transmittance from different altitudes to space in 2370 to 2390cm^-1 was calculated and analyzed. The radiations of high-temperature CO₂ located in different altitudes in the same wave range were compared. According to the variation of atmosphere and the spectral characteristic of hot CO₂, the way for choosing band of detection was discussed.

Video sequence fusion has a high request on real-time. A new fusion method of infrared and visible video fusion is proposed, which has the characteristics of low computational complexity and noise suppression. Firstly the improved mixed frame difference method is used to achieve the separation of the infrared target areas and the background areas. Secondly the new fusion algorithm is proposed to fuse the target areas of the infrared and visible light sequence. By image smoothness operator , the source images are divided into two parts: the edge region and the smooth region. Different fusion strategies are adopted for the different regions, can highlight the image edges and texture details more accurately and remove redundant, as well as suppressing noise. Finally, the fused target areas are combined with the background area of the visible light sequence to form the final fused image, which can avoid the high background noise of infrared sequence. The experimental results show that the proposed method not only can suppress noise effectively ,but also can acquire good fusion effects as well as achieve the real time need.

The correction method of compensation and correction of dynamic wavefront error detection - control, the system has automatic correction of environmental interference, keeping close to the diffraction limit resolution. The development of the modeling analysis, regulation and control, compensation correction technology, research and evaluation of an optimization result of imaging compensation based on adaptive system.

When ice run in the river course blocks the waterway severely, swelling will be speeded and of large scope, which will usually cause disasters. To judge the trend of ice flood and its disaster in the future, some data of ice flood, such as area, velocity and density, must be obtained timely. The velocity of ice flood can be got by analyzing the displacement and time interval of a same object in each image. The density of ice flood can be calculated from the ice area in a certain region. A precise area statistic of ice is the most important and difficult thing. In this paper, an edge extraction approach based on pulse coupled neural network is proposed to locate the edge of ice. Then, the area of ice can be obtained by the relativity between the ice and the region. The experimental results indicate that the method based on pulse coupled neural network is feasible. The extracted edge of the ice is distinct and continuous and the influence of noise on the infrared image is effectively eliminated.

In this paper we analyse the polarization imaging theory and the commonly process of the polarization imaging detection. Based on this, we summarize our many years’ research work especially in the mechanism, technology and system of the polarization imaging detection technology. Combined with the up-to-date development at home and abroad, this paper discusses many theory and technological problems of polarization imaging detection in detail from the view of the object polarization characteristics, key problem and key technology of polarization imaging detection, polarization imaging detection system and application, etc. The theory and technological problems include object all direction polarization characteristic retrieving, the optical electronic machinery integration designing of the polarization imaging detection system, the high precision polarization information analysis and the polarization image fast processing. Moreover, we point out the possible application direction of the polarization imaging detection technology both in martial and civilian fields. We also summarize the possible future development trend of the polarization imaging detection technology in the field of high spectrum polarization imaging. This paper can provide evident reference and guidance to promote the research and development of the polarization imaging detection technology.

The readout integrated circuit (ROIC) is a bridge between the infrared focal plane array (IRFPA) and image processing circuit in an infrared imaging system. The ROIC is the first part of signal processing circuit and connected to detectors directly, so its performance will greatly affect the detector or even the whole imaging system performance. With the development of CMOS technologies, it’s possible to digitalize the signal inside the ROIC and develop the digital ROIC. Digital ROIC can reduce complexity of the whole system and improve the system reliability. More importantly, it can accommodate variety of digital signal processing techniques which the traditional analog ROIC cannot achieve. The analog to digital converter (ADC) is the most important building block in the digital ROIC. The requirements for ADCs inside the ROIC are low power, high dynamic range and small area. In this paper we propose an RC hybrid Successive Approximation Register (SAR) ADC as the column ADC for digital ROIC. In our proposed ADC structure, a resistor ladder is used to generate several voltages. The proposed RC hybrid structure not only reduces the area of capacitor array but also releases requirement for capacitor array matching. Theory analysis and simulation show RC hybrid SAR ADC is suitable for ADC array applications

Local-sky star recognition algorithm is a process of recognizing the extracted stars in image by making use of the prior rough attitude of star sensor in celestial sphere. In order to improve the detection and response performance of star sensor working in dynamic condition, ICCD is applied to imaging stars. However, image taken by ICCD has more non-Gaussian noise and the energy of imaging star is unstable. So a local-sky star recognition algorithm using spatial triangular relationship as matching features is supposed to deal with the difficulties. In the first place, an index array is designed according to Guide Triangles, which is applied to construct Guide Triangle Index List. In the second place, a general directing range of star sensor boresight is calculated according to FOV of star sensor and the output of inertial guidance system, and then, the candidate Guide Triangles set in above region is obtained rapidly. In the third place, construct image triangle patterns by applying position and energy of the extracted stars in the image, and then match the image triangle patterns with the above candidate Guide Triangles set for two stages, until N(N≥2) groups of successfully matched triangles pairs with smallest matching deviations sum are obtained. At the last, the recognized Guide Stars have to be matched posterior referring to the principle of simulated sky image, and the recognition results of image stars are all obtained. The proposed algorithm has compact Guide Database structure, rapid local-sky guide triangles obtaining, and good recognition correction percentage, even it has worse star location precision and more false stars. The simulation tests are performed to validate the relative efficiency and adaptation of the algorithm.

With the sustaining development of application requirements in infrared technology, modern infrared imaging system demands high frame rates, wide dynamic range, high spatial resolution and high sensitivity. Because it is impossible to integrate hundreds of pF capacitor in the limited area of detector pixel, the integration time of infrared staring imaging system will be restricted. Therefore, the underutilization of detector performance is unavoidable. Specially, long wave infrared detector must accommodate stronger infrared signal, and the integration capacitor is more easily saturated. For the sake of resolving the restriction of integration capacitor, an infrared image superframing technique based on high-speed digital transmission circuit is presented in this paper. Meanwhile, the mass raw data high-speed transmission from detector to imaging circuit is also capable via the proposed technique. With the usage of the technique, the signal to noise ratio (SNR) of infrared imaging system will be improved, and the dynamic range of infrared imaging system will be also extended. The theory analysis and results of simulation demonstrate that the proposed method is feasible and effective.

A wavelength tunable optical filter based on cascaded Liquid-Crystal Fabry-Perot (LC-FP) cavity with many working units has been proposed and simulated in this paper. By choosing different material and according geometric parameters, we simulated the structure in the wavelength of medium infrared (IR)(3-5μm) and far IR(8-14μm) with the algorithm of thin film matrix equation and iterative finite-difference. Finally, we give the spectrum of the structure under different driving-voltage. Combing this structure with uncooled infrared focal plane array (IRFPA), the image of many spectral bands can be obtained in one picture frame by applying different driving-voltage on each unit. Compared with other design, this structure has the advantages of wide free spectral range (FSR), compact integration, low cost and high stability.

The infrared radiation change of the solar panels is an obvious feature to tell whether they are working normally or not. In this paper, the calculation model of the satellite's solar panels infrared feature is established. First, combined with the parameter descriptions of the satellite's six orbital elements and with the use of the coordinate transformation method, the calculation formulas of the radiation flux that the solar panels get from the sun and the earth are derived, no matter which location of the satellite in orbit. Second, the calculation model of the solar panels' temperature field is established, and the equations are solved numerically with the boundary condition of radiation heat flux. Finally, the calculation models of the solar panels' infrared radiation in 3~5μm band and 8~14μm band are established, and the equations are solved numerically, thinking differently about their radiation and reflected radiation.

With the rapid development of infrared focal plane array detector, stirling cyrocooler as a cold source has played an important role in space application. However, it is difficult to qualify its reliability and life expectancy before space application. Existing experiment and research data show that the most critical factor to restrict stirling cryocooler’s service life is working gas contamination. Based on outgassing of stirling cryocooler internal material and its relationship with temperature, time and outgassing experimental data, the failure life model of contamination is proposed. By thousands of hours of accelerated life test, two types of prototype cryocooler have been verified for applicability of the proposed life model, and the working gas analysis of tested cryocoolers also proved the existence of contamination. Afterwards, through three group contaminations adding experiment of different level water vapor, the degradation characteristics of more than 1000 hour have proved complying with the life model above. Finally, the paper further verified the applicability of this model by the fitting of experimental data of long-term running in working condition. Consequently, the life model of stirling cryocooler caused contamination degradation is established, as well as an accelerated lifetime evaluation technique was proposed for stirling cryocooler.

The star’s centroid plays a vital role in celestial navigation, star images which be gotten during daytime, due to the strong sky background, have a low SNR, and the star objectives are nearly submerged in the background, takes a great trouble to the centroid localization. Traditional methods, such as a moment method, weighted centroid calculation method is simple but has a big error, especially in the condition of a low SNR. Gaussian method has a high positioning accuracy, but the computational complexity. Analysis of the energy distribution in star image, a location method for star target centroids based on multi-step minimum energy difference is proposed. This method uses the linear superposition to narrow the centroid area, in the certain narrow area uses a certain number of interpolation to pixels for the pixels’ segmentation, and then using the symmetry of the stellar energy distribution, tentatively to get the centroid position: assume that the current pixel is the star centroid position, and then calculates and gets the difference of the sum of the energy which in the symmetric direction(in this paper we take the two directions of transverse and longitudinal) and the equal step length(which can be decided through different conditions, the paper takes 9 as the step length) of the current pixel, and obtain the centroid position in this direction when the minimum difference appears, and so do the other directions, then the validation comparison of simulated star images, and compare with several traditional methods, experiments shows that the positioning accuracy of the method up to 0.001 pixel, has good effect to calculate the centroid of low SNR conditions; at the same time, uses this method on a star map which got at the fixed observation site during daytime in near-infrared band, compare the results of the paper’s method with the position messages which were known of the star, it shows that :the multi-step minimum energy difference method achieves a better effect.