Proceedings Volume 10256

Second International Conference on Photonics and Optical Engineering

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Proceedings Volume 10256

Second International Conference on Photonics and Optical Engineering

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Volume Details

Date Published: 17 May 2017
Contents: 2 Sessions, 171 Papers, 0 Presentations
Conference: Second International Conference on Photonics and Optical Engineering 2016
Volume Number: 10256

Table of Contents

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Table of Contents

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  • Front Matter: Volume 10256
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Front Matter: Volume 10256
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Front Matter: Volume 10256
This PDF file contains the front matter associated with SPIE Proceedings Volume 10256, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and Conference Committee listing.
icPOE16 Proceedings
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Design of the optical structure of airfield in-pavement LED runway edge lights
Xiaodan Ma, Jianhong Yang, Jun Peng, et al.
Airfield lighting system is an important aiding system of civil aviation airport that guarantees the taking off, landing, taxiing of airplanes at night, with low visibility, or under other complicated weather conditions. In-pavement LED runway edge lights, with the highest degree of light intensity, are the most important lights for safe civil aviation and are most difficult to design within airfield lighting system. With LED as the source of light and the secondary optical design as the core, in light of basic laws of Fresnel loss and total reflection and the principles of edge-ray etendue conservation and the conservation of energy to design major optical elements as lens, prism of the lamp, the in-pavement LED runway edge lights design successfully solves the designing problem of high-power, high-intensity LED airfield lights with narrow beam angle at closed environment. This success is of great significance for the improvement of LED airfield lighting system in China.
Predicting the 1s core level spectroscopy of BP using the first principles
The 3D model of BP was built, the supercell model of BP was rebuilt, and created a core hole on a boron atom and the phosphorus atom using supercell model of BP. The 1s core level spectroscopy of BP with and without a core hole have been calculated using the first principles by simulation. Studying on the 1s core level spectroscopy of BP with and without a core hole, the core hole effects were investigated by comparison of the 1s core level spectroscopy of BP with and without a core hole. The core hole effects affect peak position and the width of energy of the 1s core level spectroscopy for BP. The core hole effects is that the peak position moves toward low energy and the width of energy becomes smaller.
ADRC system of FSM for image motion compensation
Kaidi Wang, Xiuqin Su, Zhe Li, et al.
In order to increase the speed controlling accuracy of fast steering mirror (FSM) for image motion compensation and thus to increase the definition of picture taken by moving camera, active disturbance rejection control (ADRC) is designed. First, mathematical model of FSM driven by voice coil motor (VCM) is established. Next, ADRC algorithm and its simplified form in actual application are clarified. Finally, simulation research for controlled object is made. The result is compared to control effect of PID. Simulation curves demonstrate that the settling time of ADRC is 6 ms and the bandwidth of system attains 102.2 Hz, which are nearly the same as those of PID. When the error is very small, it can converge to zero at a faster rate if ADRC is used. When the same range disturbance is given to system, the relative error of ADRC reaches 0.050%, which is about 42% of that of PID.
Influence of structural parameters on the laser precision tracking turntable
Erfang Cao, Wenji She, Liang Zhou
The laser tracker is composed of a mechanical structure and a servo control system. And the characteristics of them all affect the error and stability of the laser tracker measurement system. In the dynamic characteristics, the mechanical structure has its natural frequency and the servo control system has servo bandwidth. If the natural frequency closes to the servo bandwidth, the noise produced by system will have an influence on the stability and measure precision of the turntable. In order to make a laser tracker take a good performance, the natural frequency has to stay away from the range of the servo bandwidth. Based on this relationship between the natural frequency and servo bandwidth, construct and simplify a 3D model, analyze the influence of material stiffness, friction and rotary inertia on the natural frequency of a self-developed laser tracker turntable. Analysis shows that the natural frequency augments with the increase of material stiffness and reduction of rotary inertia and has nothing to do with friction. And factors of the structure material influence the different orders of natural frequency differently. These conclusions show that the kind of material with low density and high stiffness is more fitted to the turntable and provide references for optimization design of precision laser tracking turntable.
Gap solitons in partially parity-time-symmetric optical lattices
The existence and stability of gap solitons are investigated in the semi-infinite gap of a partially parity-timesymmetric two-dimensional periodic potential (optical lattice), which is invariant under complex conjugation and reflection in a single spatial direction. Firstly we study the Bloch bands and band gaps of this partially parity-time-symmetric optical lattice. We find the partially parity-time-symmetric optical lattice can still possess all-real spectra and the phase transition point remains unchangeable. Secondly, we investigate the fundamental solitons in the semi-infinite gap of the partially parity-time-symmetric optical lattice. We get the continuous families of fundamental solitons, which own the same partial parity-time-symmetry as the partially parity-timesymmetric optical lattice. Thirdly, we study the linear stability of the fundamental solitons we have got. We also investigate nonlinear evolution of the partially parity-time solitons under perturbation. It has been found that the stable domains of fundamental solitons in the partially parity-time-symmetric optical lattices are bigger than those in parity-time-symmetric optical lattices.
Development of IR imaging system simulator
Xinglang Xiang, Guojing He, Weike Dong, et al.
To overcome the disadvantages of the tradition semi-physical simulation and injection simulation equipment in the performance evaluation of the infrared imaging system (IRIS), a low-cost and reconfigurable IRIS simulator, which can simulate the realistic physical process of infrared imaging, is proposed to test and evaluate the performance of the IRIS. According to the theoretical simulation framework and the theoretical models of the IRIS, the architecture of the IRIS simulator is constructed. The 3D scenes are generated and the infrared atmospheric transmission effects are simulated using OGRE technology in real-time on the computer. The physical effects of the IRIS are classified as the signal response characteristic, modulation transfer characteristic and noise characteristic, and they are simulated on the single-board signal processing platform based on the core processor FPGA in real-time using high-speed parallel computation method.
Hybrid cylinder-triangle plasmonic waveguide for low loss propagation and subwavelength confinement
In this paper, we design and analyze a novel hybrid cylinder-triangle plasmonic waveguide (HCTSPPs), which is composed of three high index dielectric cylinders placed above an equilateral triangular metal with the center corresponding to the three vertices of the triangle. The strong hybridization coupling between Si dielectric cylinders (SDCs) and the metallic triangular wedge SPP (WSPPs) enables enhanced field confinement inside the gap region as well as long propagation length. It is also shown that relative long propagation length (100 λ ) and ultra-small deep subwavelength effective mode area (λ2/4000) can be realized by gradual modification of the geometric size, which is one-order improvement compared to other hybrid waveguides. Moreover, an investigation of the effects of actual fabrication errors on the mode properties about HCTSPPs indicates that mode properties are also quite tolerant to fabrication deviations. The proposed waveguide could be applied to subwavelength laser devices and optically integrated circuits.
Numerical study of the Bessel beams carrying optical vortices propagating in turbulent atmosphere
In this paper, the aperture averaged scintillations of the Bessel beams carrying optical vortices propagating in turbulent atmosphere are evaluated. The multistep form of the propagation algorithm and a numerical phase screen simulation method are applied to the calculations of the aperture averaged scintillation. The results show that the Bessel beam with more topological charges delivers the smaller scintillation. The relation between the aperture averaged scintillation and the size of the beams is investigated. The effect of inner and outer scales of turbulence on the scintillations of the Bessel beams is also studied. These results may be useful in long-distance optical communications in free space or in turbulent atmosphere.
Terahertz spectral detection of potassium sorbate in milk powder
The spectral characteristics of potassium sorbate in milk powder in the range of 0.2~2.0 THz have been measured with THz time-domain spectroscopy(THz-TDS). Its absorption and refraction spectra are obtained at room temperature in the nitrogen atmosphere. The results showed that potassium sorbate at 0.98 THz obvious characteristic absorption peak. The simple linear regression(SLR) model was taken to analyze the content of potassium sorbate in milk powder. The results showed that the absorption coefficient increases as the mixture potassium sorbate increases. The research is important to food quality and safety testing.
A novel long-range hybrid insulator-metal-insulator plasmonic waveguide with tight light confinement
Sheng Qu, Lu Dong, Congcong Ma, et al.
The paper presents a novel long-range hybrid insulator-metal-insulator (IMI) plasmonic waveguide, which is composed of two silicon wedge nanowires and a cylinder metal nanowire. Compared with other hybrid plasmonic waveguide, the proposed waveguide shows better properties. With strong coupling between the silicon nanowire mode and long-range surface plasmon polariton (SPP) mode, both deep subwavelength mode confinement and low propagation loss have been achieved. The properties of the hybrid IMI plasmonic waveguide including propagation length (L), normalized mode area (Aeff /A0) and figure of merit (FoM) are evaluated. Compared with the hybrid plasmonic waveguides, the designed waveguide enables an ultra-small deep-subwavelength mode in smaller area. The propagation length is nearly 1mm and FoM is ~104, which is larger than that of wedge or rectangle hybrid plasmonic waveguides. We also evaluate the impacts of practical fabrication imperfections on the mode properties. The results show that the proposed waveguide is fairly tolerant to the practical fabrication errors in geometry parameters. The proposed waveguide has many potential applications for nano-photonic components of high performance.
Modal analysis of collimation frame fabricated by titanium alloy
Yongqiang Zhang, Zhaohui Liu, Zhiguo Li
Collimation frame is the key supporting component of Space two-dimensional turntable. Its stiffness characteristics are vital for the performance of turntable. In order to reduce weight and improve rigidity, a lightweight collimation frame is designed. Compared with some commonly used aerospace materials, titanium alloy is chosen as the material of collimation frame for its excellent advantages. Modal analysis of the collimation frame is realized by using finite element analysis software MSC. Patran /Nastran to verify whether the stiffness of frame meet the design requirements. The results of analysis show that the first natural frequency of collimation frame is 169.5Hz, which satisfies the design requirement of stiffness. Then, modal experiment is conducted to verify the correctness of the results obtained from finite element modal analysis. The results of experiment show that simulation and experiment results agree well, which further confirm the correctness of the finite element modal analysis. Therefore, it proves that the selection of material and the design of structure are feasible.
Least square support vector machine for citrus greening by use of near infrared spectroscopy
Citrus greening or Huanglongbing (HLB) is one of most serious citrus diseases in the world. Once a tree is infected, there is no cure. The feasibility was investigated for discriminating citrus greening by use of near infrared (NIR) spectroscopy and least square support vector machine (LS-SVM). The spectra of sound and citrus greening samples were recorded in the wavenumber range of 4000-9000 cm-1. The preprocessing method of second derivative with a gap of seven was adapted to eliminate spectral baseline. The spectral variables were optimized by principal component analysis (PCA) and (UVE) algorithms. The unknown samples were used to access the performance of the models. Compared to the PLS-DA model, the LS-SVM was better with the input vector of the first 15 principal components and linear kernel function. The regularization factor (γ) of linear kernel function was 1.8756, and the operation time of LS-SVM model was 0.86s. The recognition error of the LS-SVM model was zero. The results showed that the combination of LS-SVM and NIR spectroscopy could detect citrus greening nondestructively and rapidly.
Fiber optic grating inscription over splice interface for strain and temperature measurement
Shuan-min Zhang, Qi Wu, An-feng Chen, et al.
A novel fiber Bragg grating(FBG) with three reflection wavelengths is proposed and demonstrated experimentally by simply phase-mask-based grating inscription over the splice interface between a thin-core fiber (TCF) and a standard single-mode fiber (SMF). The key to the success of this device lies in the refractive index differences between SMF, TCF and splice interface, and the precisely localized grating inscription over the three regions. The reflection wavelengths present different sensitivities to temperature and strain, making it as a good candidate for the measurements of two parameters simultaneously.
Theoretical study on affecting factors on squeezing level in the generation and detection of squeezed light
Fei Feng, Jiang M. Xu, Jing T. Ma, et al.
We analyze the influence factors that affect the observed degree of squeezing in generation and detection stages theoretically, including the fluctuations of pump power, the intra-cavity loss of the optical parametric amplifier (OPA) cavity , the phase fluctuation on balanced homodyning stage, the propagation efficiency, the mode matching efficiency, the out-put mirror transmission of the OPA cavity and the quantum efficiency of the detector. The theoretical results show that different loss sources appearing at various stages of the squeezed light generation and detection are far more dominant and in the end limit the squeezing level achievable. The analysis of these parameters will be extremely useful for subsequent experiments.
Experimental study on auto-focusing and ranging based on light-field imaging technique
Jiang M. Xu, Shi Y. Hu, Fei Feng, et al.
In this paper, we present an auto-focusing and ranging method which is based on light-field imaging spatial refocusing principles and simulation algorithm. The clearest image could be chosen among the refocused image sequences by using image-resolution evaluation functions when we select the window of the object whose distance needs to be measured. Finally, we measure an object on the scene with the auto-focusing and ranging method and analyze its range and accuracy. The experimental results show that the auto-focusing and ranging method could obtain distance information of different objects using one-shooting light-field image and then measure the distances of two or more objects in one scene.
Design of ocular for optical sight with long exit pupil distance
In order to solve the injury of optical sight to shooters, which is produced by recoil for using artillery or firearms, and the usage problems of shooters’ eye mask, headband and gas mask, the ocular with long exit pupil distance has been designed based on optical sighting system. The optical properties and aberration characteristics of ocular with long exit pupil distance has been analyzed, the structural style with positive-positive-negative three lens groups has been put forward. According to the aberration theory and the isoplanatic image formation principle, the focal power assignment expression has been deduced by adopting analytical method. By using of optical design software ZEMAX, the ocular with long exit pupil distance has been designed, the focal length of system is 20mm, the exit pupil diameter is 4mm, the field angle is 40°, the distance of exit pupil is 41mm, and the relative eye relief is greater than 2. The design results show if this method has been adopted, the transfer functions of each field are all greater than 0.15 when the ocular with long exit pupil distance locates on 45lp/mm, which can meet the use requirements of visual optical instruments.
Full Stokes spectralpolarimeter based on the polarization-difference interference imaging spectrometer
The theoretical operation and experimental demonstration of a Fourier-transform Stokes imaging spectropolarimeter are presented. It is composed of two birefringent crystal retarders with equal thickness (the frontal retarder is rotatable) and a Fourier-transform spectrometer based on Savart polariscope. The polarized light enters the spectrometer to create three sets of interferograms, where the spectral Stokes parameters can be calculated and acquired. Compared with previous instruments, the significant advantages of the described sensor are no spatial aliasing in the polarized spectra and it can be used in wider spectral coverage with low cost, ultra-compact size and a simpler common-path configuration.
Projection matrix acquisition for cone-beam computed tomography iterative reconstruction
Fuqiang Yang, Dinghua Zhang, Kuidong Huang, et al.
Projection matrix is an essential and time-consuming part in computed tomography (CT) iterative reconstruction. In this article a novel calculation algorithm of three-dimensional (3D) projection matrix is proposed to quickly acquire the matrix for cone-beam CT (CBCT). The CT data needed to be reconstructed is considered as consisting of the three orthogonal sets of equally spaced and parallel planes, rather than the individual voxels. After getting the intersections the rays with the surfaces of the voxels, the coordinate points and vertex is compared to obtain the index value that the ray traversed. Without considering ray-slope to voxel, it just need comparing the position of two points. Finally, the computer simulation is used to verify the effectiveness of the algorithm.
Fringe projection profilometry based on the best phase sensitivities
In fringe projection profilometry, the phase sensitivity of a fringe pattern to depth variation of the measured surface is vital to measurement accuracy and resolution. This paper represents the implementation of the optimal fringe pattern with the best phase sensitivities over the whole fringe pattern, and deduces an efficient calibration method to determine the relationship between the phase-difference distribution and the depth variation. In it, first we find the epipole location by projecting sets of horizontal and vertical fringe patterns on several depth-known reference planes, and meanwhile determine the parameters of the measurement system calibration by analyzing the geometry of measurement system. And then project the optimal fringe pattern onto the object to measure. Experimental results demonstrate that this method is very efficient and easy to implement.
Analysis of noise reduction performance with the rotated diffuser in Fizeau interferometer of a large aperture
Jiaying Zhang, Hongjun Wang, Xueliang Zhu, et al.
Since the coherent noise affected the quality of the Fizeau’s interferograms in the large aperture, the coherence of the beam was changed by rotated diffuser to reduce the noise of the interfering system. The relationships between the frequency of the rotated diffuser, the contrast of the fringes and the SNR of the system were simulated. Then, the control parameters of rotated diffuser would be required in the optimum interference fringe. The interference images were obtained under different control parameters, and the fringe contrast and system SNR of each image were analyzed. The results showed that the contrast can be reduced by choosing the proper frequency of the rotated diffuser in a certain extent, but the SNR can be improved effectively and it was convenient to process the interference image later.
Optical butting of linear infrared detector array for pushbroom imager
High resolution and large FOV represents the developing trends of space optical imaging systems, Considering the characters of infrared optical systems, A low cost and low technical risk method of optical butting concept which offer the promise of butting smaller arrays into long linear detector assemblies is presented in this paper, the design method of optical butting is described, and a hypothetical system is demonstrated as well.
Uncertainty change in length conversion affected by change in environmental parameters
The national standard of length in Japan changed to a femtosecond optical frequency comb (FOFC) in July 2009. The center frequency of the FOFC standard is 1560 nm, which is in the transmission band (C-band) of the communication optical fiber. Thanks to this fact, through the communication fiber networks, an FOFC can be delivered to everywhere at anytime. That means everyone at everywhere may access the high-accuracy length standard via communication fiber networks at anytime.

An FOFC is a stabilized pulse laser. In other words, an FOFC is a phase-coherent combination of several hundreds of thousands of wavelengths. Therefore, this fact means that there are several hundreds of thousands of different wavelengths and their combination, adjacent pulse repetition interval length (APRIL), which can be used as a length scale. Based on this idea, we proposed the APRIL-based method. APRIL-based length measurement method uses an APRIL (the physical length associated with the pulse repetition period) as a ruler for measuring distance. In this work, we show how the uncertainty in length conversion is affected by the change in environmental parameters via the sensitivity coefficients of refractive index under an actual experimental environment.
Frequency stabilization of DFB laser via modulation transfer spectroscopy
Fengxiang Yu, Jun Ruan, Xinliang Wang, et al.
We demonstrate frequency stabilization of DFB laser via modulation transfer spectroscopy, which avoids the interference of Doppler absorption spectrum. By modulating the frequency of laser beam(pump laser beam), the other laser beam(probe laser beam) overlap pump laser beam is modulated as the same frequency by nonlinear interaction. By demodulating the signal from detection beam, an error signal is generated through the low pass filter. The frequency is stabilized at the 0 point position of the MTS frequency discrimination curve by PID loop which shows frequency fluctuation is less than 149 kHz, and the relative frequency stability is improved by nearly two orders of magnitude.
Research of the metamaterial on the Chinese map
In order to overcome the problem of the larger energy loss of the metamaterial, the random curve model for the Chinese map is analyzed and discussed, which can make the metamaterial more living and simplicity. The prism and suppression samples for the Chinese map are designed, and the computer simulation and experimental test are carried out. The experimental results show that the metamaterial has a good negative refraction effect at a certain frequency, especially, both the negative refraction frequency band and the transmittance of the suppression sample for the Chinese map are improved greatly compared with the conventional model. This work provides an theoretical and practical guidance for the design and engineering of the metamaterial with a novel cycle structure.
Effects of substrate temperature on properties of vanadium oxide thin films on Si substrate
We prepared the vanadium oxide thin films on Si substrates by magnetron sputtering , using different substrate temperatures, 300℃, 350℃, 400℃. The effects of substrate temperature on film composition, micro morphology, resistance temperature characteristics, TCR (temperature coefficient of resistance) and other thin film characteristics were analyzed by XRD (X-Ray Diffraction), FESEM (Field emission scanning electron microscopy), and four-probe method. Results show that the increase of substrate temperature is conducive to the promotion of V2O5 (101) crystal formation in the films, meanwhile it is beneficial to reduce the gap and improve the uniformity of grain size, so as to increase the density of the films. The variation range of the film resistance was 500~1700 KΩ·cm,200~550 KΩ· cm and 30~160 KΩ· cm when the substrate temperature was 300 ℃ ,350 ℃ and 400 ℃ . With the increase of substrate temperature, the room temperature resistance and high temperature resistance of the thin film are greatly reduced, and the TCR performance has been optimized at the same time. The room temperature TCR of the film is about -2.4%/℃ under 400 ℃ substrate temperature, and the average TCR is about -1.98%/℃ in the process of temperature change.
Optical system design with common aperture for mid-infrared and laser composite guidance
Xuanzhi Zhang, Zijian Yang, Ting Sun, et al.
When the field of operation of precision strike missiles is more and more complicated, autonomous seekers will soon encounter serious difficulties, especially with regard to low signature targets and complex scenarios. So the dual-mode sensors combining an imaging sensor with a semi-active laser seeker are conceived to overcome these specific problems. Here the sensors composed a dual field of view mid-infrared thermal imaging camera and a laser range finder have the common optical aperture which produced the minization of seeker construction. The common aperture optical systems for mid-infrared and laser dual-mode guildance have been developed, which could meet the passive middle infrared high-resolution imaging and the active laser high-precision indication and ranging. The optical system had good image quality, and fulfilled the performance requirement of seeker system. The design and expected performance of such a dual-mode optical system will be discussed.
Imaging through strongly scattering media with subwavelength resolution and good anti-noise performance
We have proposed a novel scattered light computation microscopy (SLCM) that takes use of scattered light in imaging objects shaded by strongly scattering media. Based on the principle of light reciprocity, image is formed through computation in the SLCM method. Compared to the conventional scattered light fluorescence microscopy (SLFM) method, the SLCM doesn’t need any pretreatment of objects. Simulation results have shown that subwavelength resolution can be achieved through the SLCM with optimized parameters. The good anti-noise capability of the SLCM is demonstrated by simulation as well.
Efficient method of Shack-Hartmann wavefront sensor assembly
Xiaobin Zhou, Yadong Luan, Ke Zhou, et al.
The distance between the charge couple-device (CCD) and the micro lens array is one of assembling errors which affects the accuracy of Hartmann-Shack wavefront detector. The correction of this motion assembly parameter can effectively reduce the wavefront detector error. The relationship between the subaperture spot centroid shift amount, caused by the spherical wavefront passing through the micro lens, and the structural parameters of wavefront sensor was derived theoretically. By utilizing the relationship, defined an assembly parameter to guide the assembly process. Experiments verified the rationality of theoretical derivation then achieved a sample Hartmann-Shack wavefront sensor. This method can not only guide the Hartmann-Shack assembly quickly, but also improve the measurement accuracy of wavefront sensor.
Influence analysis of satellite drift angle on spectrum recovery precision of large aperture static interferometer spectrometer
Large aperture static interferometer spectrometer (LASIS) use the method of push-boom to get the geometric and spectral characteristics of ground target, the particularity of principle requires the movement of satellite must be in the same direction with spectrometers detectors. Drift angle of satellite leading to abnormal image shifts in the column direction which should be perpendicular to the detector and can seriously affect the spectrum recovery precision of collected data. This paper analyzes the influence mechanism of drift angle for spectrum recovery precision. Simulation based on the actual on-orbit data analyses the effects of different drift angle of relative mean deviation and relative secondary deviation rehabilitation of the spectrum, besides the influence of spectral angle similarity. These studies have shown that, when the lateral deviation due to the drift angle on the across track is less than 0.3 pixel, the effect for the relative mean deviation of the inversive spectra will be no more than 7%. when the lateral deviation due to the drift angle on the across track is larger than one pixel, even though the resampling correction is proceeded, the restored spectral data cube still shows an relative mean error more than 10%, which seriously affect the availability of spectral data.
Design of linearization double-linkage IR zoom lens
Nanxi Wang, Xiaobai Jiang, Yulan He, et al.
A linearization double-group linkage zoom lens was presented based on the 640×512 cooled FPA. This configuration’s zoom groups and compensate groups are moved linear zing, omit zoom cam which control the movement of zoom curve make common double-linkage zoom lens easily. This configuration is similarity to optical compensate zoom has a little image displacement, but it is not influence the image quality when the image displacement control in allow range. This lens was placed at cold shield and 100% cold shield efficiency had reached. Moreover, detailed design and image quality were given by CODE optical software. After analysis, MTF approaches diffraction limit. The results show that this optical system has large zoom ratio, and excellent image quality.
Optical design of laser zoom projective lens with variable total track
Yulan He, Xiangguo Xiao, Feng Lu, et al.
In order to project the laser command information to the proper distance , so a laser zoom projective lens with variable total track optical system is designed in the carrier-based aircraft landing system. By choosing the zoom structure, designing of initial structure with PW solution, correcting and balancing the aberration, a large variable total track with 35~× zoom is carried out. The size of image is invariable that is φ25m, the distance of projective image is variable from 100m to 3500m. Optical reverse design, the spot is less than 8μm, the MTF is near the diffraction limitation, the value of MTF is bigger than 0.4 at 50lp/mm.
The design of common aperture and multi-band optical system based on day light telescope
Jiao Chen, Ling Wang, Bo Zhang, et al.
As the development of electro-optical weapon system, the technique of common path and multi-sensor are used popular, and becoming a trend. According to the requirement of miniaturization and lightweight for electro-optical stabilized sighting system, a day light telescope/television viewing-aim system/ laser ranger has been designed in this thesis, which has common aperture. Thus integration scheme of multi-band and common aperture has been adopted. A day light telescope has been presented, which magnification is 8, field of view is 6°, and distance of exit pupil is more than 20mm. For 1/3" CCD, television viewing-aim system which has 156mm focal length, has been completed. In addition, laser ranging system has been designed, with 10km raging distance. This paper outlines its principle which used day light telescope as optical reference of correcting the optical axis. Besides, by means of shared objective, reserved image with inverting prism and coating beam-splitting film on the inclined plane of the cube prism, the system has been applied to electro-optical weapon system, with high-resolution of imaging and high-precision ranging.
Parallel transformation of K-SVD solar image denoising algorithm
The images obtained by observing the sun through a large telescope always suffered with noise due to the low SNR. K-SVD denoising algorithm can effectively remove Gauss white noise. Training dictionaries for sparse representations is a time consuming task, due to the large size of the data involved and to the complexity of the training algorithms. In this paper, an OpenMP parallel programming language is proposed to transform the serial algorithm to the parallel version. Data parallelism model is used to transform the algorithm. Not one atom but multiple atoms updated simultaneously is the biggest change. The denoising effect and acceleration performance are tested after completion of the parallel algorithm. Speedup of the program is 13.563 in condition of using 16 cores. This parallel version can fully utilize the multi-core CPU hardware resources, greatly reduce running time and easily to transplant in multi-core platform.
The infrared bands Pechan prism axis parallel detection method
Hua Qiang, Ming Ji, Yu-lan He, et al.
In this paper, we put forward a new method to adjust the air gap of the total reflection air gap of the infrared Pechan prism. The adjustment of the air gap in the air gap of the Pechan prism directly affects the parallelism of the optical axis, so as to affect the consistency of the optical axis of the infrared system. The method solves the contradiction between the total reflection and the high transmission of the infrared wave band, and promotes the engineering of the infrared wave band. This paper puts forward the method of adjusting and controlling, which can ensure the full reflection and high penetration of the light, and also can accurately measure the optical axis of the optical axis of the different Pechan prism, and can achieve the precision of the level of the sec. For Pechan prism used in the infrared band image de rotation, make the product to realize miniaturization, lightweight plays an important significance.
Structural optimization of the path length control mirror for ring laser gyro
Yanghua Ma, Bingxin Quan, Zonghu Han, et al.
The path length control mirror (PLCM) is essential for high precision ring laser gyro (RLG). In this paper the influence of the structural parameters of the PLCM on its length compensating efficiency (LCE) and the anti-transversedeformation capability(ATDC) is numerically investigated, with the aid of the finite element software ANSYS. The result shows that the inner and outer diameters as well as the thickness of the deformation slot of the PLCM have significant influences on both its LCE and ATDC, while the position of the deformation slot of the PLCM has little impact on its LCE and mainly affect its ATDC. According to the simulation, two types of PLCMs with the same parameters all but the position of deformation slot are fabricated and experimentally demonstrated, with the result showing great agreement with the simulation. That is to say, for a given overall dimension constraint, the dynamic stability of the RLG resonator can be dramatically enhanced by a proper design of the PLCM, without almost any negative impact on its LCE. This will be of great value for the optimization of the PLCM for RLG, especially for miniature RLG.
Simulation design of light field imaging based on ZEMAX
Ke Zhou, Xiangguo Xiao, Yadong Luan, et al.
Based on the principium of light field imaging, there designed a objective lens and a microlens array for gathering the light field feature, the homologous ZEMAX models was also be built. Then all the parameters were optimized using ZEMAX and the simulation image was given out. It pointed out that the position relationship between the objective lens and the microlens array had a great affect on imaging, which was the guidance when developing a prototype.
Comparison of monomode KTiOPO4 waveguide formed by C3+ ion implantation and Rb+ ion exchange
Xiao-Jun Cui, Liang-Ling Wang
In this work, we report on the formation and characterization of monomode KTiOPO4 waveguide at 1539 nm by 6.0 MeV C3+ ion implantation with the dose of 2×1015 ions/cm2 and Rb+-K+ ion exchange, respectively. The relative intensity of light as a function of effective refractive index of TM modes at 633 nm and 1539 nm for KTiOPO4 waveguide formed by two different methods were compared with the prism coupling technique. The refractive index (nz) profile for the ion implanted waveguide was reconstructed by reflectivity calculation method, and one for the ion exchanged waveguide was by inverse Wentzel–Kramers–Brillouin. The nuclear energy loss versus penetration depth of the C3+ ions implantation into KTiOPO4 was simulated using the Stopping Range of Ions in Matter software. The Rutherford Backscattering Spectrometry spectrum of KTiOPO4 waveguide was analyzed after ions exchanged. The results showed that monomode waveguide at 1539 nm can be formed by ion implantation and Rb+ -K+ ion exchange, respectively.
Influence of photoelectric detector on the dynamic range of laser seeker
Juan Hao, Junwei Ma, Zongzhe Zhao, et al.
Based on the influence of the sensitivity and gain control of the photoelectric detector on the dynamic range of the laser seeker, a method for improving the dynamic range of the laser seeker was presented. Firstly the test for measuring the saturated amplitude was built, The influence of sensitivity and saturation amplitude on dynamic range of seeker were obtained; Secondly the relationship between sensitivity, saturation amplitude, gain control and dynamic range were analyzed in theory, and the method for avoiding the saturation of the detector in the process of gain control was designed. The results indicated the method that avoided output voltage of the detector saturated in advance could meet the 5V gain control of the seeker with a dynamic range of more than 90dB.
An adaptive Gamma method for image under non-uniform illumination
Zefeng Wang, Haifeng Zhang, Jiawen Liao, et al.
Gamma correction is a necessary operation for a digital image before it is sent to display. Uneven illumination images have low resolution and a lot of information is covered. In order to better removal of light effects and reproduce truly plain circumstances, this paper presents a new local adaptive gamma correction method. The experiment shows this method makes the brightness distribution more uniform and proved that the method compared with other methods that have better correction results.
Principle component analysis based hyperspectral image fusion in imaging spectropolarimeter
Wenyi Ren, Dan Wu, Jiangang Jiang, et al.
Image fusion is of great importance in object detection. A PCA based image fusion method was proposed. A pixel-level average method and a wavelet-based methods have been implemented for a comparison study. Different performance metrics without reference image are implemented to evaluate the performance of image fusion algorithms. It has been concluded that image fusion using PCA based method showed better performance.
Ultra-short wavelength operation in Thulium-doped silica fiber laser with bidirectional pumping
Xusheng Xiao, Haitao Guo, Zhijun Yan, et al.
An ultra-short wavelength operation of Tm-doped all fiber laser based on fiber Bragg gratings (FBGs) was developed. A bi-directional pump configuration for the ultra-short wavelength operation was designed and investigated for the first time. the laser yielded 3.15W of continuous-wave output at 1706.75nm with a narrow-linewidth of ~50pm and a maximum slope efficiency of 42.1%. The dependencies of the slope efficiencies and pump threshold of the laser versus the length of active fiber and reflectivity of the output mirror (FBG) were investigated in detail. An experimental comparative study between two Thulium-doped fiber lasers (TDFLs) with two different pumping configuration(forward unidirectional pumping and bidirectional pumping) was presented. It is indisputable that the development of 1.7μm silicate fiber lasers with Watt-level output power open up a number of heart-stirring and tempting application windows.
Spectrum analysis of radar life signal in the three kinds of theoretical models
X. F. Yang, J. F. Ma, D. Wang
In the single frequency continuous wave radar life detection system, based on the Doppler effect, the theory model of radar life signal is expressed by the real function, and there is a phenomenon that can’t be confirmed by the experiment. When the phase generated by the distance between the measured object and the radar measuring head is л of integer times, the main frequency spectrum of life signal (respiration and heartbeat) is not existed in radar life signal. If this phase is л/2 of odd times, the main frequency spectrum of breath and heartbeat frequency is the strongest. In this paper, we use the Doppler effect as the basic theory, using three different mathematical expressions——real function, complex exponential function and Bessel's function expansion form. They are used to establish the theoretical model of radar life signal. Simulation analysis revealed that the Bessel expansion form theoretical model solve the problem of real function form. Compared with the theoretical model of the complex exponential function, the derived spectral line is greatly reduced in the theoretical model of Bessel expansion form, which is more consistent with the actual situation.
A new method named as Segment-Compound method of baffle design
Xing Qin, Xiaoxu Yang, Xin Gao, et al.
As the observation demand increased, the demand of the lens imaging quality rising. Segment- Compound baffle design method was proposed in this paper. Three traditional methods of baffle design they are characterized as Inside to Outside, Outside to Inside, and Mirror Symmetry. Through a transmission type of optical system, the four methods were used to design stray light suppression structure for it, respectively. Then, structures modeling simulation with Solidworks, CAXA, Tracepro, At last, point source transmittance (PST) curve lines were got to describe their performance. The result shows that the Segment- Compound method can inhibit stay light more effectively. Moreover, it is easy to active and without use special material.
Dual-wavelengths photoacoustic temperature measurement
Yu Liao, Xiaohua Jian, Fenglin Dong, et al.
Thermal therapy is an approach applied in cancer treatment by heating local tissue to kill the tumor cells, which requires a high sensitivity of temperature monitoring during therapy. Current clinical methods like fMRI,near infrared or ultrasound for temperature measurement still have limitations on penetration depth or sensitivity. Photoacoustic temperature sensing is a newly developed temperature sensing method that has a potential to be applied in thermal therapy, which usually employs a single wavelength laser for signal generating and temperature detecting. Because of the system disturbances including laser intensity, ambient temperature and complexity of target, the accidental errors of measurement is unavoidable. For solving these problems, we proposed a new method of photoacoustic temperature sensing by using two wavelengths to reduce random error and increase the measurement accuracy in this paper. Firstly a brief theoretical analysis was deduced. Then in the experiment, a temperature measurement resolution of about 1℃ in the range of 23-48℃ in ex vivo pig blood was achieved, and an obvious decrease of absolute error was observed with averagely 1.7℃ in single wavelength pattern while nearly 1℃ in dual-wavelengths pattern. The obtained results indicates that dual-wavelengths photoacoustic sensing of temperature is able to reduce random error and improve accuracy of measuring, which could be a more efficient method for photoacoustic temperature sensing in thermal therapy of tumor.
The propagation characteristics of circular Airy beam with low-pass filtering modification
The propagation characteristics of the circular Airy beam (CAB) modified with low-pass filtering is investigated in details in this paper. Based on a modification of the angular spectrum of CAB, we get a new kind of CAB constructed with low frequency spectrum, which is called “LCAB” for short. A suitable low-pass filter is introduced to cut off the high frequency angular spectrum and maintain the low frequency domain mainly affecting the front light rings of CAB. Two apodization parameters are employed to optimize the low-pass filtering, which influence the propagation characteristic of the LCAB. Fortunately, the abruptly autofocusing property, the most important property of CAB, is still maintained in LCAB. What is more, the initial ring number and the focal spot length can be controlled by adjusting the two apodization parameters. If the two apodization parameters are appropriately chosen, one can form an elegant optical needle which plays an important role in optical manipulations. The numerical results show that the less front light rings are, the longer the optical needle is. It should be noted that the width of the optical needle will increase as long as the length increases, and lead to the decline of the maximum intensity of the optical needle.
Automatic phase aberration compensation and imaging of digital holographic microscopy
Xing Wang, Hong-wei Ma, Dou-dou Wang, et al.
The accuracy of numerical reconstruction phase directly affect the result of the digital holographic detection. Because the microscope objective causes additional secondary phase factor, resulting in phase distortion of the reconstructed image. In order to find the phase distortion present in the reconstruction process and take the appropriate way to achieve automatic compensation of phase, digital holographic microscopy in phase compensation issues are studied. Least-squares curve fitting method and choose a background profile data approach is employed to produce the phase mask, and several iterations of correction of mask data by profile data. The theoretical analysis and experimental comparison of this method was validated. The results show that this method can quickly and accurately for better phase distortion correction, while providing new ideas for efficient extraction of real phase.
Fast recovery method for fog image
Zefeng Wang, Hongtao Yang, Hui Zhang, et al.
The images of outdoor scenes obtained in haze, fog and other weather phenomena are usually have poor contrast and color fidelity. In order to get a clear view of the image taken under bad weather, this paper for the image degradation in fog and haze, we detailed analyzed the image degradation causes and fuzzy mechanism and made some meaningful work for improving the existing defogging method and introduing new ideas. The experimental results demonstrate the new method abilities to remove the haze layer as well as provide a reliable depth map.
Optical humidity detection based on tunable diode laser absorption spectroscopy
Keke Zhang, Shixuan Liu, Shizhe Chen, et al.
Humidity is an important environmental parameter, which is difficult to be measured accurately and quickly using traditional measurement methods. Under the environment of low temperature or high humidity, traditional humidity and temperature sensor has shortages in humidity measurement accuracy, corresponding time and wet fade speed. To solve these problems, this paper proposes a method to measure the environmental humidity with wavelength modulation technology and harmonic detection technology based on tunable diode laser absorption spectroscopy. H2O molecular absorption line near 1392 nm is selected as the characteristic spectra. The effects of temperature, pressure and water concentration on the absorption spectrum width, the wavelength modulation coefficient and the amplitude of the harmonic signal are analyzed. Humidity and temperature sensor is modified using temperature and pressure compensation model, and the influence of the water concentration variation is eliminated by the iterative algorithm. The new humidity and temperature sensor prototype is developed, and the structure of the optical system is simple, which is easy to be adjusted. The response frequency of the humidity detection is 40 Hz. The experiment was carried out for 3 months at Qingdao national basic weather station. Experimental results show that the consistency of the humidity and temperature data is very good, which can proves the validity of the humidity measurement technology.
Numerical simulation and experimental research of using spherical reference wavefront to test aspheric surface
Qiwei Wang, Tao Sun, Shen Dong, et al.
A practical aspheric non-null testing method of combining numerical simulation with real interferometric testing was proposed. Numerical simulation and analysis of using three typical spherical reference wavefronts which emitted by the interferometer (hereinafter referred to as spherical reference wavefronts) to test ideal aspheric surface were carried out by MATLAB. According to simulation results (simulated interferograms), the smallest one of wavefront aberrations between ideal aspheric surface and three typical spherical reference wavefronts, respectively, was selected as the wavefront under test for aspheric full aperture test; in this case, the theoretical interferogram of aspheric non-null testing was obtained by adding an appropriate amount of tilt and defocus amount to the wavefront under test. According to the theoretical interferogram, a real testing interferogram of an aspherical reflector with a diameter of 110 mm (the maximum asphericity to the vertex sphere is 6.8μm) was obtained quickly by visual observation by Zygo interferometer, and the aspheric machining error was obtained by a series processing of testing data extraction and Zernike polynomials fitting etc.. Comparison with the aspheric testing results of Taylor Hobson profilometer shows that the difference of PV and RMS value errors is less then 0.08μm and 0.02μm, respectively.
Numerical analysis of thermally tunable liquid-crystal-filled terahertz fiber
Doudou Wang, Hongwei Ma, Lili Wang, et al.
A liquid-crystal-filled polymer photonic crystal fiber is designed and numerically analysised for terahertz wave guiding. Bandgap-guiding terahertz fiber is obtained by infiltrating the cladding air holes of index guiding Topas photonic crystal fiber with liquid crystal 5CB. Structural parameter dependence and thermal tunability of the photonic bandgaps, mode properties and confinement losses of the designed fiber are investigated by using the finite element method. The bandgaps are formed based on antiresonances of the individual liquid crystal inclusions, so the positions of bandgaps depend strongly on the cladding hole diameter and weakly on the lattice constant. Bandgaps and the positions of the confinement loss minimum or peaks of the transmission spectra shift toward lower frequency as temperature increased from 25 °C to 34 °C due to the positive dno/dT of 5CB. Average thermal tuning sensitivity of -30 GHz/°C is achieved for the designed fiber. At the central frequency of the transmission band, high power transmission coefficient and thus low splicing loss between the aligned liquid-crystal-filled polymer photonic crystal fiber and the unfilled section is obtained. Our results provide theoretical references for applications of liquid-crystal photonic crystal fiber in sensing and tunable fiber-optic devices in terahertz frequencies.
Er3+ doped Pb(Mg1/3Nb2/3)O3-0.25PbTiO3 transparent ceramic: a multi-functional material for photonics switching and temperature measurement
Zhang Liang, Zhiguo Zhang, Guorong Li, et al.
We have successfully prepared the Er3+ doped Pb(Mg1/3Nb2/3)O3-0.25PbTiO3 (PMN-PT) transparent ceramic by a two ways sintering method. Through studying the green fluorescence originating from 2H11/2 and 4S3/2 under different electric field, we found that the prepared sample could be enhanced by electric field by 150%, this phenomenon is reversible so it could be used for photonics switching devices in further application. Moreover, the fluorescence intensity ratio of 2H11/2 and 4S3/2 was studied under different temperature. Unlike the usually exponential response, the FIR here shows a linear response to changing temperature. So an easier temperature measurement method was developed by using Er3+ doped PMN-PT transparent ceramic as detector.
Research on electromechanical resonance of two-axis tracking system
Zhi-ming Zhao, Ying-jie Xue, Shu-qin Zeng, et al.
The multi-axes synchronous system about the spatial two-axis turntable is the key equipment for semi-physical simulation and test in aerospace. In this paper, the whole structure design of the turntable is created by using Solidworks, then putting the three-dimensional solid model into ANSYS to build the finite element model. The software ANSYS is used to do the simulation about the static and dynamic analysis of two-axis turntable. Based on the modal analysis, we can forecast the inherent frequencies and the mode of vibration during the launch conditions which is very important to the design and safety of the structure.
Inter-satellites x-ray communication system
An inter-satellite X-ray communication system is presented in this paper. X-ray has a strong penetrating power without almost attenuation for transmission in outer space when the energy of X-ray photons is more than 10KeV and the atmospheric pressure is lower than 10-1 Pa, so it is convincing of x-ray communication in inter-satellite communication and deep space exploration. Additionally, using X-ray photons as information carriers can be used in some communication applications that laser communication and radio frequency (RF) communication are not available, such as ionization blackout area communication. The inter-satellites X-ray communication system, including the grid modulated X-ray source, the high-sensitivity X-ray detector and the transmitting and receiving antenna, is described explicitly. As the X-ray transmitter, a vacuum-sealed miniature modulated X-ray source has been fabricated via the single-step brazing process in a vacuum furnace. Pulse modulation of X-rays, by means of controlling the voltage value of the grid electrode, is realized. Three focusing electrodes, meanwhile, are used to make the electron beam converge and finally 150μm focusing spot diameter is obtained. The X-ray detector based on silicon avalanche photodiodes (APDs) is chosen as the communication receiver on account of its high temporal resolution and non-vacuum operating environment. Furthermore, considering x-ray emission characteristic and communication distance of X-rays, the multilayer nested rotary parabolic optics is picked out as transmitting and receiving antenna. And as a new concept of the space communication, there will be more important scientific significance and application prospects, called “Next-Generation Communications”.
Optimal design of an earth observation optical system with dual spectral and high resolution
Pei-pei Yan, Kai Jiang, Kai Liu, et al.
With the increasing demand of the high-resolution remote sensing images by military and civilians, Countries around the world are optimistic about the prospect of higher resolution remote sensing images. Moreover, design a visible/infrared integrative optic system has important value in earth observation. Because visible system can’t identify camouflage and recon at night, so we should associate visible camera with infrared camera. An earth observation optical system with dual spectral and high resolution is designed. The paper mainly researches on the integrative design of visible and infrared optic system, which makes the system lighter and smaller, and achieves one satellite with two uses. The working waveband of the system covers visible, middle infrared (3-5um). Dual waveband clear imaging is achieved with dispersive RC system. The focal length of visible system is 3056mm, F/# is 10.91. And the focal length of middle infrared system is 1120mm, F/# is 4. In order to suppress the middle infrared thermal radiation and stray light, the second imaging system is achieved and the narcissus phenomenon is analyzed. The system characteristic is that the structure is simple. And the especial requirements of the Modulation Transfer Function (MTF), spot, energy concentration, and distortion etc. are all satisfied.
Study of fuzzy PID controller for velocity circuit of optical-electronic theodolite
GengXin Li, XiaoJun Yang, SaiXian He
Two-axis stabilized turntable is an important part of optical-electronic theodolite, it carries various of measuring instruments. In order to improve the response speed of the optical-electronic theodolite when tracking high speed target. In the same time, improve the stability and precision when tracking low speed target. The traditional servo controller is double close-loop structure. On the basis of traditional structure, we use the fuzzy control theory to design the servo control speed loop adjuster as a fuzzy PID controller, and the position loop is designed as a traditional first order adjuster. We introduce the theory and characteristics of PID control and fuzzy control, and discussed the structure of the speed loop fussy controller and the tuning method of the PID parameters. The fuzzy PID controller was studied with simulation on the MATLAB/Simulink platform, the performance indexes and the anti-jamming abilities of the fussy PID controller and the traditional PID controller were compared. The experiment results show that the fussy PID controller has the ability of parameter self-tuning, and its tacking ability is much better than the traditional PID controller.
A micro displacement measurement method based on PGC demodulation of space optics
Zhenyu Xiong, Xudong Yu, Xingwu Long, et al.
An improved interferometric system aiming at measuring micro displacement is put forward on the basis of phase generated carrier(PGC) demodulation of space optics. This system can improve the accuracy of Absolute Gravimeter(AG) by measuring the amplitude and direction of ground vibration. While the carrier frequency is between 1K and 2K, ground vibration with low frequency (10Hz to 100Hz) and micro vibration amplitude (30nm to 300nm) can be obtained, which satisfies the requirements of AG.
Calibration on the detection efficiency of the Si-APD and InGaAs-APD single-photon detectors by correlated photon pairs
Xueshun Shi, Kun Zhao, Changming Liu, et al.
We demonstrated calibration on the detection efficiency of Si-avalanche photodiode (APD) and InGaAs-APD singlephoton detectors by correlated photon pairs at 780 nm and 1550 nm, respectively. The correlated photons were generated by spontaneous frequency down-conversion in a periodically poled potassium titanyl phosphate crystal (PPKTP) pumped by a pulsed fiber laser. The uncertainty of ~10-4 on detection efficiency was obtained for both single-photon detectors.
Design of the intelligent smoke alarm system based on photoelectric smoke
Jiangfei Ma, Xiufang Yang, Peipei Wang
This paper designed a kind of intelligent smoke alarm system based on photoelectric smoke detector and temperature, The system takes AT89C51 MCU as the core of hardware control and Labview as the host computer monitoring center.The sensor system acquires temperature signals and smoke signals, the MCU control A/D by Sampling and converting the output analog signals , and then the two signals will be uploaded to the host computer through the serial communication. To achieve real-time monitoring of smoke and temperature in the environment, LabVIEW monitoring platform need to hold, process, analysis and display these samping signals. The intelligent smoke alarm system is suitable for large scale shopping malls and other public places, which can greatly reduce the false alarm rate of fire, The experimental results show that the system runs well and can alarm when the setting threshold is reached,and the threshold parameters can be adjusted according to the actual conditions of the field. The system is easy to operate, simple in structure, intelligent, low cost, and with strong practical value.
Mechanism and experimental research on ultra-precision grinding of ferrite
Xinxing Ban, Huiying Zhao, Longchao Dong, et al.
Ultra-precision grinding of ferrite is conducted to investigate the removal mechanism. Effect of the accuracy of machine tool key components on grinding surface quality is analyzed. The surface generation model of ferrite ultra-precision grinding machining is established. In order to reveal the surface formation mechanism of ferrite in the process of ultraprecision grinding, furthermore, the scientific and accurate of the calculation model are taken into account to verify the grinding surface roughness, which is proposed. Orthogonal experiment is designed using the high precision aerostatic turntable and aerostatic spindle for ferrite which is a typical hard brittle materials. Based on the experimental results, the influence factors and laws of ultra-precision grinding surface of ferrite are discussed through the analysis of the surface roughness. The results show that the quality of ferrite grinding surface is the optimal parameters, when the wheel speed of 20000r/mm, feed rate of 10mm/min, grinding depth of 0.005mm, and turntable rotary speed of 5r/min, the surface roughness Ra can up to 75nm.
Movement decoupling control for two-axis fast steering mirror
Based on flexure hinge and piezoelectric actuator of two-axis fast steering mirror is a complex system with time varying, uncertain and strong coupling. It is extremely difficult to achieve high precision decoupling control with the traditional PID control method. The feedback error learning method was established an inverse hysteresis model which was based inner product dynamic neural network nonlinear and no-smooth for piezo-ceramic. In order to improve the actuator high precision, a method was proposed, which was based piezo-ceramic inverse model of two dynamic neural network adaptive control. The experiment result indicated that, compared with two neural network adaptive movement decoupling control algorithm, static relative error is reduced from 4.44% to 0.30% and coupling degree is reduced from 12.71% to 0.60%, while dynamic relative error is reduced from 13.92% to 2.85% and coupling degree is reduced from 2.63% to 1.17%.
Analysis and compensation of disturbance for small inertial stabilized Line-of-Sight system
One of the main factors that affect the performance of stabilized Line-of-Sight (LOS) control system is disturbance torque. Firstly, the transfer function between disturbance torque and angular velocity of LOS is given by establishing the system dynamics model. Secondly, we investigate the characteristics of disturbance torque for small inertial Line-of-Sight control system. Thirdly, an application of disturbance observer is presented to compensate for disturbance, such as friction and mass imbalance. In this paper, consider only friction. Simulation is made by using the friction model output as disturbance input. In the course of Matlab simulation, the compensation by using disturbance observer improves the overall stabilization performance of the system. The RMS value of the velocity error has decreased to 10%.
Research of the wavefront detection method based on the scanning pentaprism
Xueliang Zhu, Huiying Zhao, Longchao Dong, et al.
With the rapid developing of science and technology, large aperture optical system plays an important role in the hightech fields including space optics, astronomical optics, inertial confinement fusion, the detecting and recognizing of space target. However, the problems of the wavefront sensing about large aperture optical system has been totally solved because of the equipment expenses and long manufacturing periods. In order to test the large aperture elements in optical system with cheaper costs and higher resolution, more and more attentions are paid into the wavefront sensing of large aperture optical systems. The scanning pentaprism system is introduced to divide the wavefront of the interferometer into a series of sub-wavefront, and the relative positions of the spot centroid accroding to every sub-wavefront are recorded on the CCD camera. The normal directions of every sub-wavefront are obtained to reconstruct the tested wavefront. Experimental results are accord with the interferometer measure results. The feasibility of the pentaprism scanning method has been validated. Finally the influences of measurement apparatus and environment on the measuring precision is discussed. Which is useful to expand the measuring range to keep high spatial resolution and reduce cost.
Control of laser wavelength tuning and its application in coherent optical time domain reflectometer
Lidong Lu, Xiaoyan Sun, Binglin Li
A laser diode temperature control scheme is adopted to achieve the laser wavelength tuning of a narrow linewidth laser, which sends commands by serial communication to change the laser diode temperature. The laser diode temperature is presented by the temperature sensitive resistance. And then the laser wavelength tuning method is also used in a coherent optical time domain reflectometer (C-OTDR) to reduce the coherent Rayleigh noise (CRN) caused by the coherence of the narrow linewidth laser. As the serial communication for the laser wavelength tuning is time-consuming which costs at least 10ms to finish the wavelength tuning once, the measurement time and efficiency of the C-OTDR should be considered. And then the relationship between the times for the laser wavelength changing and the CRN fluctuation is experimentally studied to balance the measurement time consumption and the measurement results, which illustrates that the laser wavelength needs not be changed in each measurement period of the C-OTDR and it can also obtain the ideal result to change the laser wavelength every 500 measurement periods. In traditional C-OTDR, by serial communication, the laser wavelength is changed in each measurement period and the total measurement periods are 218, so by the new scheme it can save about 2600 seconds to achieve an ideal measurement, which is of high efficiency.
The analysis of bit error ratio for self-homodyning coherent detection system
Xiaoyang Jia, Shoufeng Tong, Xiaoyan Li, et al.
BER measures the accuracy of data transmission within specified time, which is an important parameter to evaluate the performance of communication system. First, this paper analyzes the influence factors of BER for DPSK self-homodyning coherent detection system such as modulation format, atmospheric turbulence, coherent demodulation. We take it into consideration that atmospheric channel will affect the transmission signal ,simulated the DPSK self-coherent detection system in different weather conditions and analyzed the results. The simulation results shows that the bit error rate of 10 Gb/s self-coherent detection system reaches 10-10 ,when the weather condition is light haze. It indicates that self-coherent detection system has great potential in satellite-ground laser communication.
Influence study of parameters to holographic interference pattern by computer simulation
We report the simulation of photonic crystals by holographic interference. In this article, different parameters such as azimuth angle, polarization angle, incident angle and phase degree are discussed, and the influences of them to interference patterns are studied. For 3 + 1 beams, the incidence angle influent the structure period, the phase degree doesn’t influent interference structure, the azimuth angle and polarization can change the structure. The azimuth angle change makes triangle claw structure elongate and intercourse and the polarization makes the contrast change. The simulation result paves a way for the optimized fabrication of structures by holographic lithography.
Study of thin film thickness measurement based on white light interference
One method for measuring thin film thickness was proposed in this paper, which based on white light interference. One parallel flat crystal was used to be the standard glass, and put another glass on it, to form one air wedge between them. The reflectance spectrum of two beams interference was measured by one spectrometer. By fitting the reflectance spectrum, wave numbers corresponding to every peak can be found, then using two beam interference theory, the air gap thickness at light incident point can be fitted. By measuring the air gap thickness at different positions, the flatness of measured surface also can be analyzed.
Acceleration sensing based on graphene resonator
Wenbin Jie, Feng Hu, Xingshu Wang, et al.
This paper is concerned with the acceleration sensing based on graphene resonator using finite-element software COMSOL Multiphysics. Based on the ordinary graphene resonator structure, a proof mass is attached to the surface of graphene sheet in order to sense acceleration and force more effectively. The rectangle-shaped gold proof mass is positioned at the center of the graphene sheet. Through COMSOL Multiphysics, the simulations about how the graphene sheet and mass’ dimension affect resonance frequency were performed and proper size parameters for the graphene resonator were chosen. By adopting these parameters, the analysis about the resonance frequency’s change responding to the acceleration or working force was carried out, which lays a foundation for further research of graphene resonator for acceleration sensing.
FPGA implement method for two-dimensional integer wavelet transform in the space-based on-orbit image compression system
Jie Wang, Yan Tian, Xiangsheng Meng, et al.
The image obtained from space-based vision system has increasingly high frame frequency and resolution, and field of view is also growing. Due to the dramatic increase of data scale and the restriction of channel bandwidth between satellite and ground, on-orbit data compression becomes the core of on-satellite data processing. The paper analyzes the new generation static image compression standard JPEG2000 and the key two-dimensional (2D) discrete wavelet transform (DWT) technology. Then an FPGA (Field Programmable Gate Array)implement method for 2D integer wavelet transform is designed. It adopts the spatial combinative lifting algorithm (SCLA), which realizes the simultaneous transformation on rows and columns. On this basis, the paper realizes wavelet decomposition for images with a resolution of 6576*4384 (which is divided into 1024*1024) on the FPGA platform. In particular, the test platform is built in ISE14.7 simulation software, and the device model is xc5vfx100t. The design has passed the FPGA verification. In order to verify the correctness of the algorithm, the results are compared with that obtained by running matlab code. The experimental results show that the design is correct and the resource occupancy rate is low.
The cooling control system for focal plane assembly of astronomical satellite camera based on TEC
The dark current noise existing in the CCD of the astronomical observation camera has a serious influence on its working performance, reducing the working temperature of CCD can suppress the influence of dark current effectively. By analyzing the relationship between the CCD chip and the dark current noise, the optimum working temperature of the red band CCD focal plane is identified as -75℃. According to the refrigeration temperature, a cooling control system for focal plane based on a thermoelectric cooler (TEC) was designed. It is required that the system can achieve high precision temperature control for the target. In the cooling control system, the 80C32 microcontroller was used as its systematic core processor. The advanced PID control algorithm is adopted to control the temperature of the top end of TEC. The bottom end of the TEC setting a constant value according to the target temperature used to assist the upper TEC to control the temperature. The experimental results show that the cooling system satisfies the requirements of the focal plane for the astronomical observation camera, it can reach the working temperature of -75℃ and the accuracy of ±2℃.
Design and analysis of micro stress flexible support structure of reflector in all day star tracker
Yang Liu, Su Chen, Lingguang Wang, et al.
To reduce the surface deformation of a star tracker reflector in a complex and execrable environment, a micro stress flexible support structure was designed according to the circular optical reflector subassembly. By defining the thickness, width and radius as design variables, the flexible hinge in an circular reflector subassembly was optimized. Then, the surface figure precision, structural strength and dynamic stiffness of the reflector subassembly in the thermal-structural coupling state were analyzed with the finite element method. Simulation results show that the natural frequency of the reflector is enough, which has a sufficiently high dynamic stiffness. Both surface precision RMS of the reflector (8.34nm, 9.26nm) have reached the index requirements of the optical system (λ/10, λ=632.8nm) under gravity and uniform temperature change from -20℃ to 65℃. The results show that the design for the micro stress flexible support structure is reasonable and feasible, and achieves the design goal.
Improved image quality of digital lithography using modified particle swarm optimization algorithm
Liang Zhang, ZhaoJun Shi, Qishen Li
Image distortion problem is key issue in DMD digital lithography system, in this paper, quality optimization algorithm of digital lithography based on improved particle swarm optimization algorithm is proposed. The fidelity is adopted as the fitness function. The pixels in the mask pattern are used as particles, and then optimization is implemented by updating the velocities and positions of these particles. Two different graphs are used to verify the method, image quality optimization of the standard particle swarm optimization algorithm and the steepest descent gradient descent algorithm, the pattern errors are reduced by 95.48%, 91.95% and 92.78%, 87.28%, respectively. The quality of image is improved, and the convergence speed is faster.
A dual-direction fringe projection method for the 3D measurement of translucent object
Huijie Zhao, Xiaoyue Liang, Hongzhi Jiang, et al.
The fringe projection technology is widely used in 3D measurement fields. However when the technology is applying to translucent objects, the subsurface scattering and absorbing always leads to a decline of the measurement accuracy. The aim of this paper is to propose a dual-direction fringe projection method in order to obtain an more accurate measurement result for the translucent objects as while as change the whole measurement system little and do not reduce the measuring rapidity. The paper mainly includes three parts: (1) The principle of dual-direction fringe projection method and different forms of dual-direction fringe; (2) Analysis of the different effect for the measurement accuracy brought by different factors; (3) Experiments for artificial tooth by various dual-direction fringes and accuracy analysis. The experiment results showed that by this method it is possible to improve the measurement accuracy for the translucent objects.
The 3D measurement techniques for ancient architecture and historical relics
Huijie Zhao, Xiaochun Diao, Hongzhi Jiang, et al.
Nowadays, 3D measurement and re-construction technologies are widely used not only in industry area, but also in the appreciation and research of ancient architecture and historical relics. Many methods are used for the architecture measurement in large scale, but as for the details of architecture or precision historical relics, these methods meet difficulties. Thus, historical relic objects with specular surface or complex sculptural surface could not be measured by traditional method. Focusing on these problems, this paper proposed 3D measurement technique which contains two levels of measurement. Firstly, when measuring ancient architecture in large scale, laser scanning and photometry methods are used. Then, when measuring details of architecture, a fast and adaptive 3D measurement system is used. Multi-view registration is also used for the measurement of hollowed-out structure of sculptural relics. The experiments indicate that the system can achieve 3D measurement and re-construction of different types of ancient architecture and historical relics.
Investigation of grinding parameters and machine dynamic characteristics' effect towards brittle material subsurface damage
B. Li, Y. Y. Wu, J. P. Xi, et al.
Elements performance is greatly affected by their surface and subsurface integrity, especially for the brittle material. Prediction model of the subsurface damage would provide the insight into the grinding parameters effects and better control of them. In this paper, based on the classic brittle solid crack theory, prediction model of brittle material subsurface damage induced by brittle mode diamond grinding was established. Firstly, contact area calculation was modeled to estimate the involved grits number using the grit density. Based on the prediction model, grinding parameters effects were investigated. Finally, grinding machine stiffness, accuracy and damping coefficients were introduced to quantitatively analyze their effects towards subsurface damage. The proposed model would promote more definite control of grinding induced subsurface damage and optimal design of the grinding machine dynamic characteristics.
High-accuracy measurement and compensation of grating line-density error in a tiled-grating compressor
Dan Zhao, Xiao Wang, Jie Mu, et al.
The grating tiling technology is one of the most effective means to increase the aperture of the gratings. The line-density error (LDE) between sub-gratings will degrade the performance of the tiling gratings, high accuracy measurement and compensation of the LDE are of significance to improve the output pulses characteristics of the tiled-grating compressor. In this paper, the influence of LDE on the output pulses of the tiled-grating compressor is quantitatively analyzed by means of numerical simulation, the output beams drift and output pulses broadening resulting from the LDE are presented. Based on the numerical results we propose a compensation method to reduce the degradations of the tiled grating compressor by applying angular tilt error and longitudinal piston error at the same time. Moreover, a monitoring system is setup to measure the LDE between sub-gratings accurately and the dispersion variation due to the LDE is also demonstrated based on spatial-spectral interference. In this way, we can realize high-accuracy measurement and compensation of the LDE, and this would provide an efficient way to guide the adjustment of the tiling gratings.
Dispersion characteristics of Tellurite glass photonic crystal fiber
Mingzhu Jiang, Baoxing Xiong, Guiju Zhang, et al.
In this paper, we have fabricated the tellurite glass (70TeO2-20ZnO-5Al2O3-5La2O3, mol%, TZAL) by using high temperature melting method. Considering the material dispersion, the dispersion properties of TZAL glass photonic crystal fiber (PCFs) for various structures are analyzed and precisely described based on the vector finite element method (FEM). A novel structure with three-ring TZAL Glass PCF is proposed by introducing large elliptical holes in the inner ring. The simulation results show that ZDW decreases from 1.586μm to1.485μm when the numbers of elliptical holes increases from two to six. ZDW of horizontally disposed ellipses of PCF is a litter lower than that of vertically positioned ellipses. Furthermore, with optimizing parameters of pitch period and diameter of air hole, ZDW is reduced to 1.396μm. The dispersion characteristics can be flexibly designed and adjusted. The approach and results can be guidance for design, manufacture the photonic crystal fibers.
Accelerating hyper-spectral data processing on the multi-CPU and multi-GPU heterogeneous computing platform
Lei Zhang, Jiao Bo Gao, Yu Hu, et al.
During the research of hyper-spectral imaging spectrometer, how to process the huge amount of image data is a difficult problem for all researchers. The amount of image data is about the order of magnitude of several hundred megabytes per second. The only way to solve this problem is parallel computing technology. With the development of multi-core CPU and GPU,parallel computing on multi-core CPU or GPU is increasingly applied in large-scale data processing. In this paper, we propose a new parallel computing solution of hyper-spectral data processing which is based on the multi-CPU and multi-GPU heterogeneous computing platform. We use OpenMP technology to control multi-core CPU, we also use CUDA to schedule the parallel computing on multi-GPU. Experimental results show that the speed of hyper-spectral data processing on the multi-CPU and multi-GPU heterogeneous computing platform is apparently faster than the traditional serial algorithm which is run on single core CPU. Our research has significant meaning for the engineering application of the windowing Fourier transform imaging spectrometer.
Research on spot of CCD subdivided locating methods in laser triangulation displacement measurement
Hongjun Wang, Lei Hui, Jiaying Zhang
In order to improve the measurement accuracy of the laser displacement sensor, the laser triangulation displacement measuring system is established. The spot subdivision location algorithms of the system are studied, such as the Gaussian curve fitting, traditional gray weighted centroid and gray square weighted centroid. First, according to the principle of laser triangulation, the displacement measuring system is built. Then, objects are moved by the high-precision motorized stage, obtaining multiple sets of image data. Next, these data respectively are processed by the above several algorithms to obtain the corresponding coordinates of the laser spot, the system is calibrated respectively. Finally, comparing the displacement of calibration results calculating with the actual displacement. The results show that: those data that are processed by the gray square weighted centroid are used to calibrate , calculating the minimum error, and is 71.1 μm. It concludes that gray square weighted centroid is an ideal location segmentation method, which is not only simple and easy to implement, but also has a higher positioning accuracy.
Analysis of a novel device-level SINS/ACFSS deeply integrated navigation method
Hao Zhang, Shiqiao Qin, Xingshu Wang, et al.
The combination of the strap-down inertial navigation system(SINS) and the celestial navigation system(CNS) is one of the popular measures to constitute the integrated navigation system. A star sensor(SS) is used as a precise attitude determination device in CNS. To solve the problem that the star image obtained by SS is motion-blurred under dynamic conditions, the attitude-correlated frames(ACF) approach is presented and the star sensor which works based on ACF approach is named ACFSS. Depending on the ACF approach, a novel device-level SINS/ACFSS deeply integrated navigation method is proposed in this paper. Feedback to the ACF process from the error of the gyro is one of the typical characters of the SINS/CNS deeply integrated navigation method. Herein, simulation results have verified its validity and efficiency in improving the accuracy of gyro and it can be proved that this method is feasible.
A compact LWIR imaging spectrometer with a variable gap Fabry-Perot interferometer
Fourier transform spectroscopy is a widely employed method for obtaining spectra, with applications ranging from the desktop to remote sensing. The long wave infrared (LWIR) interferometric spectral imaging system is always with huge volume and large weight. In order to miniaturize and light the instrument, a new method of LWIR spectral imaging system based on a variable gap Fabry-Perot (FP) interferometer is researched. With the system working principle analyzed, theoretically, it is researched that how to make certain the primary parameter, such as, the reflectivity of the two interferometric cavity surfaces, field of view (FOV) and f-number of the imaging lens. A prototype is developed and a good experimental result of CO2 laser is obtained. The research shows that besides high throughput and high spectral resolution, the advantage of miniaturization is also simultaneously achieved in this method.
A Fabry-Perot interferometric imaging spectrometer in LWIR
With applications ranging from the desktop to remote sensing, the long wave infrared (LWIR) interferometric spectral imaging system is always with huge volume and large weight. In order to miniaturize and light the instrument, a new method of LWIR spectral imaging system based on a variable gap Fabry-Perot (FP) interferometer is researched. With the system working principle analyzed, theoretically, it is researched that how to make certain the primary parameter, such as, wedge angle of interferometric cavity, f-number of the imaging lens and the relationship between the wedge angle and the modulation of the interferogram. A prototype is developed and a good experimental result of a uniform radiation source, a monochromatic source, is obtained. The research shows that besides high throughput and high spectral resolution, the advantage of miniaturization is also simultaneously achieved in this method.
Application of linear CCD in tunnel crack detection
Jie Liu, Hua Li, Xin Jiang, et al.
To meet the actual demand, the linear CCD technology is applied to tunnel crack detection, and an edge detection algorithm is proposed to measure the crack width. Firstly, the application form of linear CCD imaging technology in tunnel crack detection is introduced concretely in this paper. Then, the key influencing parameters of measurement are discussed. Finally, an edge detection algorithm based on the change of gray level in linear direction is proposed and it is verified by experiments. Experimental results indicated that the linear CCD imaging technology in tunnel crack detection could obtain measurement data quickly and improve the efficiency of tunnel cracks’ measurement, and that the detection algorithm could be used for the crack width measuring.
A reflection polarizations zoom metasurfaces
Based on generalized Snell’s law, we propose a dual-polarity zoom metasurfaces operating electromagnetic wave in the reflection geometry. The metasurfaces is constructed by two identical ultrathin metal-backed dielectric slabs with metallic Jerusalem cross patterns on the other sides to form a triangular region. The normally incident waves are totally reflected, but the reflection phases of both x- and y-polarized waves are controlled independently. According to the classical theory of optical imaging, the reflection electromagnetic wave phases were obtained in the different polarizations and focus. Each subwavelength units size were determined with the reflection coefficient of the basic unit, the polarizations zoom metasurfaces was designed in the way. The full-wave simulations are in good agreement with theoretical analysis in microwave lengths.
Synchronous acquisition method based on feature recognition of sequence images in online vision inspection
Xin Jiang, Hua Li, Jie Liu
In order to meet the requirements of synchronous image acquisition in online industrial vision inspection, a new method based on image feature recognition is proposed. According to the method, the spatial characteristic information of sequence images has been calculated, and an algorithm under multi-constrained conditions which based on the trend of feature values of sequence images is established. The synchronous target image in online inspection is acquired by the trigger signal which was obtained by the algorithm under the condition of no dependence on external attachment. The method does not need to rely on the external position feedback device, and reduces the hardware cost. The algorithm has a better synchronization precision and adaptability, and has been successfully applied in practice.
Optimized design method for trench-assisted grade-index ring-core fiber with low DMD and large Aeff
Xihui Qiao, Jiajing Tu, Keping Long
We propose a kind of trench-assisted graded-index ring-core fiber (TA-GI-RCF) with a low refractive index rod deployed in the center of the core, which supports three LP modes (LP01, LP11 and LP21) transmission. There are two difficulties about designing TA-GI-RCF, one is to depart LP21 mode from LP02 mode because their effective indices are too close which makes it difficult to realize only three LP modes transmission; the other one is how to make sure these three LP modes reach the receiver end with low differential mode delay (DMD), so that the computation complexity of multi-input multi-output (MIMO) digital signal process (DSP) can be reduced. At first, we realize the separation of LP21 mode and LP02 mode in TA-GI-RCF by enlarging the size of low refractive index rod. We next investigate the influence of the TA-GI-RCF structural parameters on DMD and DMD slope, and find that a graded-index core and a low refractive index rod can flexibly tune the DMD, and a trench can flexibly control the DMD slope. Through optimizing the core parameters, we find that the design region of α is 1.01~2.23 and that of Δ1 is 0.28%~0.46% at r1=30 μm, where α is the profile exponent and Δ1 is the relative refractive index difference between core and cladding. Simulation results show that TA-GI-RCF can achieve the effective area (Aeff) of LP01 mode over 2000 μm2 and the |DMD| between LP01 mode and LP11 mode is ≤100 ps/km over C+L band. Above all, we can achieve three LP modes transmission in TA-GIRCF with low DMD over whole C+L band and large Aeff.
Dual-band perfect absorbers based on the magnetic resonance and the cavity resonance
An infrared (IR) absorber based on the metamaterial structure is proposed theoretically and numerically. The near-unity absorption can be achieved at a certain wavelength by optimizing geometrical parameters of the structure. Moreover, we can switch a single-band absorber to dual-band absorber by decreasing the thickness of top metallic layer which is perforated by an air-filled ribbon. At the same time, we confirm that the mechanism of this two absorption bands is completely different. The simultaneous effects of the magnetic resonance and the cavity resonance occur at our proposed structure. Besides according to the control of polarization direction, the absorption peaks occur at the two constant wavelengths, and the superposed value of this two absorption peaks is always close to a constant. Based on this phenomenon, a simple dual-band absorber is designed when the thickness of top shaped metallic film is relatively large. The cavity response is not the existence in this condition. These results that we obtain may provide some promising applications such as sensors, thermal imagers, and IR detectors.
Evolution of the Raman spectra of electron beam irradiated graphene exposed in air
Zhihao Huang, Jingyue Fang, Xiaoming Zheng, et al.
The modification of graphene’s properties is essential for its applications. During the device preparation and morphology characterization, graphene is usually irradiated by electron beam. The process may induce defects such as damage and doping in graphene. Moreover, when the irradiated graphene is exposed in air, the defects will adsorb impurities, such as gas atoms, atomic groups, or molecules, leading to changes of the properties of graphene. Therefore, it is important to study the evolution of the properties of the irradiated graphene exposed in air. In this paper, the time evolution of the Raman spectra of graphene after irradiated by electron beam was measured. It is found that D peak appears after irradiation, indicating the formation of defects. The Raman spectra at different time after irradiation show redshifts and blueshifts of the peaks, because the carriers was p-type at first and then became n-type finally. It signifies that air exposure has changed the conducting properties of the irradiated graphene. The results suggest that air exposure has significant effect on defect engineering of graphene.
A novel design of subminiature star sensor’s imaging system based on TMS320DM3730
Meiying Liu, Hu Wang, Desheng Wen, et al.
Development of the next generation star sensor is tending to miniaturization, low cost and low power consumption, so the imaging system based on FPGA in the past could not meet its developing requirements. A novel design of digital imaging system is discussed in this paper. Combined with the MT9P031 CMOS image sensor’s timing sequence and working mode, the sensor driving circuit and image data memory circuit were implemented with the main control unit TMS320DM3730. In order to make the hardware system has the advantage of small size and light weight, the hardware adopted miniaturization design. The software simulation and experimental results demonstrated that the designed imaging system was reasonable, the function of tunable integration time and selectable window readout modes were realized. The communication with computer was exact. The system has the advantage of the powerful image processing, small-size, compact, stable, reliable and low power consumption. The whole system volume is 40 mm *40 mm *40mm,the system weight is 105g, the system power consumption is lower than 1w. This design provided a feasible solution for the realization of the subminiature star sensor’s imaging system.
Automatic seamless image mosaic method based on SIFT features
Meiying Liu, Desheng Wen
An automatic seamless image mosaic method based on SIFT features is proposed. First a scale-invariant feature extracting algorithm SIFT is used for feature extraction and matching, which gains sub-pixel precision for features extraction. Then, the transforming matrix H is computed with improved PROSAC algorithm , compared with RANSAC algorithm, the calculate efficiency is advanced, and the number of the inliers are more. Then the transforming matrix H is purify with LM algorithm. And finally image mosaic is completed with smoothing algorithm. The method implements automatically and avoids the disadvantages of traditional image mosaic method under different scale and illumination conditions. Experimental results show the image mosaic effect is wonderful and the algorithm is stable very much. It is high valuable in practice.
Intelligent large diameter aspherical reflector polishing technology
Baowei Qiu, Wen Guo, Peng Wang
Large diameter aspherical reflector polishing technology is a kind of technology which has big difficulty, long process cycle and high production cost. Therefore, the polishing efficiency and accuracy are reduced. But now the intelligent large diameter aspherical reflector polishing technology greatly increases the polishing efficiency and accuracy. This paper introduces intelligent large diameter aspherical reflector polishing technology. Intelligent large diameter aspherical reflector polishing technology is a technology to make the skill of the advanced optical machining person digitization and quantization. Compared with traditional optical machining technology, intelligent optical machining technology makes the judgement of the optical shape more accurate, control of the process more reliable, machining efficiency accuracy greatly improved. Take 1.2m diameter aspherical reflector as an example. Before manufacture, PV of the mirror is 2035.531nm and RMS of the mirror is 192.392nm; After simulation, PV of the mirror is 1598.222nm and RMS of the mirror is 133.216nm; After manufacture, PV of the mirror is 1503.122nm and RMS of the mirror is 133.110nm.The PV error between simulation and manufacture is -5.95%.The RMS error between simulation and manufacture is -0.08%.These results prove that intelligent large diameter aspherical reflector polishing technology is high efficient and accurate.
Fourier transform profilometry based on mean envelope extraction
Xiaoxuan Zhang, Shujun Huang, Nan Gao, et al.
Based on an image pre-processing algorithm, a three-dimensional (3D) object measurement method is proposed by combining time domain and frequency domain analysis. Firstly, extreme points of sinusoidal fringes under the disturbance of noise are accurately extracted. Secondly, mean envelope of the fringe is obtained through appropriate interpolation method and then removed. Thirdly, phase information is extracted by using specific filtering in Fourier spectrum of the pre-processed fringe pattern. Finally, simulated and experimental results show a good property of the proposed method in accuracy and measurement range. The proposed method can achieve 3D shape of objects having large slopes and/or discontinuous surfaces from one-shot acquisition by using color fringe projection technique and will have wide applications in the fields of fast measurement.
Atmospheric transmittance of O2 (0-1) airglow
A ground based airglow imager interferometer (GBAII) has made in our group to detect the upper atmospheric temperature and wind velocity at terrestrial altitude 90-100 km. GBAII’s sources are the airglow of O (1S) 557.7 nm at altitude of 97km and O2 (0-1) 867.7nm at altitude of 94 km. a uniform value of the atmospheric transmissivity was used in the forward and inversion process of GBAII, which was led to GBAII a lower wind measurement accuracy. The atmospheric transmissivity of O2 (0-1) airglow is calculated and simulated in this paper. Based on the analysis and calculation of the high level atmospheric absorption, scattering attenuation, scattering ratio, acquire transmittance and the attenuation ratio of CO2 and water vapor are obtained by adding the methods of weighted mean, number density of molecules, different height modified segments, the different correction factors vs. different atmospheric heights etc. By MATLAB programme, the atmosphere scattering ratio is obtained to be 1.876×10-3, CO2 transmittance to be 0 and water vapor to be 0.1888, respectively. The total atmospheric transmittance of O2 (0-1) airglow is 0.4663.
Improving the atmospheric wind speed measured accuracy by the ground-based airglow imaging interferometer
Yuanhe Tang, Rui Yang, Haiyang Gao, et al.
A prototype ground based airglow imaging interferometer (GBAII) has been constructed to observe the upper atmospheric wind velocity and temperature at an altitude of 90-100 km, but the GBAII’s wind speed accuracy was found to be unsatisfactory with a value of 21.0 m/s. Three theoretical aspects have been investigated to improve the accuracy, with the following finding: 1) By replacing the surface coatings of the GBAII’s 6 lenses and Michelson interferometer (MI) with a new wind-speed infrared film rather than the original visible light film, the accuracy can be increased by 3.0 m/s. 2) By replacing the original charge-coupled device (CCD) with a quantum efficiency (QE) of 0.38 at the wavelength of approximately 866 nm by an electron multiplying CCD (EMCCD) with QE of 0.95, the accuracy can be increased by 6.7 m/s. By adding all the factors that improve the accuracy of the GBAII, it can be improved by 15.0 m/s, which realizes the original aim of wind speed accuracy of 6.0 m/s. Experimental results have been obtained for two aspects: 1) By replacing the surface film on the GBAII’s 6 lenses and MI interface, the wind speed accuracy has been increased by 3.8 m/s. 2) A new GBAII temperature controller has been constructed to control the environmental temperature in 0.2 K steps. The results obtained by the GBAII on Dec. 6, 2013 show an average atmospheric temperature of 206.5 K, zonal wind speed of -26.8 m/s and meridional wind speed of 28.1 m/s. These results are close to those of the TIMED (Thermosphere Ionosphere Mesosphere Energetics and Dynamics) satellite Doppler interferometer (TIDI) data collected at almost the same time.
Design of laser Michelson interferometer for the detection of nanolitre solution
Yangcheng Luo, Huiqing Chen, Kun Liu, et al.
By use of common optical equipment, a laser Michelson interferometer system that can be used for the detection of microfluidic chip is designed. A He-Ne laser beam (power of 0.5mW and diameter of about 0.7mm) is divided into a detection beam and a reference beam by a beam splitter. The reference beam is slightly expanded with a lens and has a diameter of about 1.5mm. A microfluidic chip with channel diameter of 60μm is placed in the detection arm of the interferometer. The detection beam falls on the channel of the chip. On the screen 1.6 meters far from the splitter, an interesting pattern containing both circular fringes and linear fringes is observed. Experiment shows obviously that the patterns on the screen are different when the channel is filled with air, pure water and the sodium hydroxide solution (with a refractive index of 1.343). It is indicated that the interferometer is effective for the detection of solutions as tiny as 3 nano liters with different refractive indices.
High voltage pulse gated power supply with adjustable pulse width
Image intensifier is the key components of low-light level night vision device. In order to extend its dynamic range of the night vision sight, a high voltage pulse gated power supply (HVPGPS) for image intensifier cathode is researched in this paper. The HVPGPS with pulse width adjustable is optimally designed for the image intensifier cathode power supply. Its pulse amplitude is 250 V, with 1 kHz frequency. Two different circuits are combined to get the adjustable pulse width from narrow to wide. The pulse width parameters are: the narrow pulse circuit is from 20 ns to 300 ns, and its wide pulse circuit is 300 ns – millisecond (ms). This HVPGPS can achieve the advantages of small size circuit, low power consumption, and which meets the requirements of image intensifier cathode power supply.
Research on transmission high sensitivity GaAs cathode of low light level image devices
Ke Xu, Kunye Han, Jiangtao Xu
To strive for the goal of further improving the overall performance of low-light-level Gen.Ⅲ image intensifier tube, modifications and innovations in the making of GaAs photocathode are already underway revolving around the basis of existing research, through which the sensitivity of GaAs photocathode is considerably improved from 1200μA/lm to above 1800μA/lm, 2000μA/lm (typical value), and it won’t drop within the 1000hrs’ storage inside the station according to the experiment on the photoemission stability of high-sensitivity GaAs photocathode. In short, highly distinguished characteristics of high sensitivity GaAs photocathode like wide response range, superior quantum efficiency and 1.06μm infrared response wavelength, promise its remarkable significance in both the enhancement of the overall performance and the prolongation of the operational life-span of low-lightlevel Gen.Ⅲ image intensifier tube.
Effect of the characteristics of beam polarization on performance of 90 degree optical hybrid
90 degree optical hybrid is the key part of space coherent optical communication and the high efficient mixing technology is an effective means to achieve great detect sensitivity. Most of optical components in optical hybrid are sensitive to polarization state, therefore, the polarization state of incident light will affect the function of hybrid. Through an theoretical analysis and simulation of the performance of hybrid whose incident light is linearly or elliptically polarized light, the result shows that the heterodyne efficiency of hybrid reaches its maximum when incident light is 45°linearly, and the change of polarization orientation can decrease the optical power entering I branch, making the heterodyne efficiency declines. Degree of polarization will increase phase difference of both branch which is orthometric in hybrid, causing the process of phase locking more difficult. Moreover, the effect of deviation of directivity of wave plate on hybrid performance is studied, for 1/4 wave plate, its deviation will change the power allegation and phase error of IandQ branch, but for 1/2 wave plate, phase error cannot be brought in, but it will change the direct current(DC) component of branch. The above polarization state changes will not bring additional phase error in I branch, ensuring the normal functioning of hybrid. This study gives a theoretical foundation to the design of space optical hybrid.
Theoretical and experimental analysis of modern zoom lens design
Xiangyang Wang, Weilin Liu
The need for stability of aberration and correction of images for a zoom lens system should be considered during zooming process. Our work presents detailed theoretical and experimental analysis of multiple moving zoom optical systems. In our work we propose methods to determine the basic parameters of such optical system, the focal lengths of each element of the objective lens and their mutual axial separation. Introduce two different image stability equation and cam curve design method to calculate basic parameters. This type of optical system is widely spread in practice mainly in the field of photographic lenses and in surveying instruments (theodolites, leveling instruments, etc.). Furthermore, the detailed analysis of aberration properties of such optical systems is performed and methods for measuring the focal lengths of individual elements and their mutual distance without the need for disassembling the investigated optical system are presented. Finally according to theoretical and experimental analysis of zoom lens system, a zoom optical system with effective focal length 27-220mm has been design, the first element of such system is fixed, and the other groups can move during zoom process to get a continuity consecutiveness effective focal length (EFL). Using the powerful optimization capabilities of optical design software CODE V; we get the imaging quality analysis such as the modulation transfer function (MTF) etc.
A novel approach of an absolute coding pattern based on Hamiltonian graph
Ya'nan Wang, Huawei Wang, Fusheng Hao, et al.
In this paper, a novel approach of an optical type absolute rotary encoder coding pattern is presented. The concept is based on the principle of the absolute encoder to find out a unique sequence that ensures an unambiguous shaft position of any angular. We design a single-ring and a n-by-2 matrix absolute encoder coding pattern by using the variations of Hamiltonian graph principle. 12 encoding bits is used in the single-ring by a linear array CCD to achieve an 1080-position cycle encoding. Besides, a 2-by-2 matrix is used as an unit in the 2-track disk to achieve a 16-bits encoding pattern by using an area array CCD sensor (as a sample). Finally, a higher resolution can be gained by an electronic subdivision of the signals. Compared with the conventional gray or binary code pattern (for a 2n resolution), this new pattern has a higher resolution (2n*n) with less coding tracks, which means the new pattern can lead to a smaller encoder, which is essential in the industrial production.
Method of improving photoelectric efficiency for laser power beaming based on photovoltaic cell layout optimization
In accordance with the high impact of the uneven distribution of laser beam power on the photovoltaic efficiency of photovoltaic cell (PV) array, a method based on PV layout optimization is proposed to improve the photovoltaic efficiency. First of all, a mathematical model of series-parallel PV array is built, and by analyzing the influencing factors on photovoltaic efficiency, the idea and scheme to improve the photovoltaic efficiency based on PV layout optimization is provided; then, the MATLAB/Simulink simulation tool is used to simulate the effects of improving photoelectric efficiency. The simulation results show that compared to the traditional PV array, the optimized PV array can obtain higher photovoltaic efficiency, and compared to the situation with uneven temperature distribution, the array efficiency has higher efficiency under even temperature distribution.
The design of fiber-based 4-LP mode multi/demultiplexer
Huan Zhang, Jiajing Tu, Keping Long
We propose a fiber-based 4-LP mode (LP01, LP11, LP21 and LP02) multi/demultiplexer, which excites or separates 4-LP mode simultaneously in the integrated structure of a single optical fiber. The structure contains a 4-mode transmitting core in the center of the fiber and the other three multi/demulitplexing parts (consist of a coupling core and several assistant cores or not) which are deployed around the transmitting core with 120 degrees between each other.

The design of the fiber-based 4-LP mode multi/demultiplexer includes the following parts. Firstly, the appropriate distance between the transmitting core and the surrounding parts are below 15μm, 12μm and 10μm for multi/demultiplexing of LP11, LP21 and LP02 mode, respectively, which can guarantee the coupling loss is less than 2%. Then we design the structural parameters (core diameter and refractive index) of single-mode coupling cores to achieve phase matching between LP01 (single-mode coupling cores) and LP11, LP21, LP02 (transmitting core), respectively. The appropriate core diameter and refractive index for the coupling cores of the multi/demultiplexing parts are 5μm and 1.465703 (LP01-LP11), 2μm and 1.479793 (LP01-LP21), 1.5μm and 1.488404 (LP01-LP02), respectively, all of which can ensure that the coupling efficiency are more than 90% in the C+L band. Afterwards, by discussing the coupling crosstalk of each multi/demultiplexing part, we find that LP02-LP01 mode multi/demultiplexing part does not need any assistant core, LP21-LP01 and LP11-LP01 mode multi/multiplexing parts need to add 1 or 2 assistant single mode core as required to decrease the coupling crosstalk. Finally by adjusting the relative position of the three multi/demultiplexing parts and the transmitting core (ensure the performance of the whole system is not affected), we can ensure that the 4 mode can be multi/demultiplexed at the same time.

Above all, we put forward a fiber-based 4-LP-mode multi/demultiplexer which excites or separates 4-LP mode simultaneously with high multi/demultiplexing efficiency, low coupling loss, and low coupling crosstalk.
Precision glass molding technology for low Tg glasses
Hong Yang, Zhibin Wang, Yunlong Zhang, et al.
Precision glass molding (PGM) technology is a cost-effective manufacturing process for high precision optical elements with complex surfaces. With this processing technology, one or more pieces of lenses may be produced through one-step molding. Due to the high efficiency of the replicative process, PGM has found wide applications in high volume production of optical elements. At present, it has been well developed and widely used in mass industry production in Japan and South Korea, but in China PGM technology research is still in the elementary stage. To develop the PGM technology, we need to conquer several technical difficulties, such as the melting technology of low Tg glasses, highprecision mold design and the corresponding machining technology and the coating technology for the molds. In this paper, we discussed the PGM technology as a complete manufacturing process, focused on the technical difficulties mentioned above, and introduced the development directions for this technology in China.
Femtosecond laser ablated durable superhydrophobic PTFE sheet for oil/water separation
Wentao Li, Qing Yang, Feng Chen, et al.
Femtosecond laser microfabrication has been attracting increasing interest of researchers in recent years, and been applied on interface science to control the wettability of solid surfaces. Herein, we fabricate a kind of rough microstructures on polytetrafluoroethylene (PTFE) sheet by femtosecond laser. The femtosecond laser ablated surfaces show durable superhydrophobicity and ultralow water adhesion even after storing in a harsh environment for a long time, including strong acid, strong alkali, and high temperature. A penetrating microholes array was further generated on the rough superhydrophobic PTFE sheet by a subsequent mechanical drilling process. The as-prepared material was successfully applied in the field of oil/water separation due to the inverse superhydrophobicity and superoleophilicity.
Ray-tracing analysis of a snapshot imaging polarimeter using modified Savart polariscopes
Jing Zhang, Qizhi Cao, Mingxian Chen, et al.
In this paper, the formula for the imaging intensity of the snapshot imaging polarimeter (SIP) using modified Savart polariscopes (MSP) is derived in detail by the ray-tracing analysis and fringe decomposition. SIP using MSP is shown to yield an improvement in the qualitative and quantitative carry frequency, signal-to-noise ratio and spatial resolution compared with SIP using conventional Savart polariscopes by the numerical simulation. This study provides a theoretical and practical guidance for study, design, modulation, experiment and engineering of SIP using MSP.
Fabrication of the asymmetric double-sided concave microlens arrays by femtosecond laser
Fan Zhang, Qing Yang, Hao Bian, et al.
In the last decades, fabrication of microlens array in materials with high-damage threshold has attracted increasing interest, especially in the application of high-power laser. In this paper, we propose an advanced strategy to efficiently fabricate microlens array on the surface of glass using a single-pulsed femtosecond laser wet etch process, which is a combination of high-speed laser scanning and the subsequent chemical etch with HF solution. Based on this method, double-sided microlens array, non-regular arrays consisting of close-packed concave microlens array on one side and regular concave MLA on the other side, were fabricated on the 1cm*1cm glass. Especially over one million microlenses could be acquired within an hour, exhibiting great superiority in practical application. Moreover, the optical properties of the asymmetric double-sided MLA were experimentally characterized, and the experimental results reveal the good light homogenization performance.
Fabrication of 3D electro-thermal micro actuators in silica glass by femtosecond laser wet etch and microsolidics
Qichao Li, Chao Shan, Qing Yang, et al.
This paper demonstrates a novel electro-thermal micro actuator’s design, fabrication and device tests which combine microfluidic technology and microsolidics process. A three-dimensional solenoid microchannel with high aspect ratio is fabricated inside the silica glass by an improved femtosecond laser wet etch (FLWE) technology, and the diameter of the spiral coil is only 200 μm. Molten alloy (Bi/In/Sn/Pb) with high melting point is injected into the three-dimensional solenoid microchannel inside the silica glass , then it solidifys and forms an electro-thermal micro actuator. The device is capable of achieving precise temperature control and quick response, and can also be easily integrated into MEMS, sensors and ‘lab on a chip’ (LOC) platform inside the fused silica substrate.
Micropatterning microlens arrays fabricated by a femtosecond laser wet etch process
Yang Wei, Qing Yang, Hao Bian, et al.
Microlens arrays with specially required micropatterns are highly desirable for digital optical processors, microimaging systems, optical photolithography as well as various biomedical imaging and detecting applications. However, realization of such devices efficiently remains technically challenging. Here, a facile and efficient route for large-area microlens arrays (MLAs) with programmable micropatterns is demonstrated. The fabrication process involves a femtosecond laser wet etch process combined with the replication process of hot embossing. Special arranged microlens arrays, including a doublet microlens array, a three-microlens group array, a four-microlens group array, and a six-petallike microlens array as examples, were fabricated by this method. The fabricated MLAs exhibit excellent surface morphology quality and optical imaging properties. This presented technique provides an efficient way to flexibly design the size, shape and the arrangement of the MLAs by adjusting the process parameters such as the pulse energy, the number of shots etching time and the distribution of ablation-induced craters and Programming arrangement.
The study of infrared quenching over LLP(Long Lag Phosphor) material
Based on the laser writing device developed by our group before, wiping the glow is necessary as a function added on the machine. This article is a theoretical and experimental study of glow wiping start from luminescence theory and infrared ray. The trap depths of ZnS: Cu and SrAl2O4:Eu2+, Dy3+ are figured out according to the TSL(thermos stimulated luminescent ) dynamics, then the accurate IR wavelength to release the trapped electrons in proper depth. We select every single wavelength of energy 1nm by 1nm from near IR and deliver it by crystal fiber. The glow fading curves of ZnS: Cu and SrAl2O4:Eu2+, Dy3+ are figured under IR. The TSL spectrum of ZnS: Cu and SrAl2O4:Eu2+, Dy3+are measured with a thermal luminescence meter. The experiment result of glow wiping has proved the theory. This paper provide a pioneer experiment and theoretical base for further study of IR quenching wavelength about more variety of LLP material.
Power build-up cavity enhanced Raman spectroscopy based on piezoelectric transducer for gas analysis
In this paper, the Power Build-Up cavity enhanced Raman spectroscopy is introduced and the matching mode between the cavity length and wavelength is improved simultaneously. At the same time, the laser diode optical frequency modulation circuit is designed. Cavity length control system is built up to enhance the cavity power and experiments are also set up. The 532nm laser is coupled into an external linear optical cavity composed of two highly reflective mirrors. Since the light source is a solid laser, center light wavelength is a constant and line width is also known. Considered the distance between concave mirrors, the cavity length is squirmed slightly by the piezoelectric transducer. The light intensity measurement method is designed to record and analyze the performance of the cavity beam power and figure out the non-linear characteristic of system. In the premise of stable initial condition of enhanced system, the operating point is searched firstly which based on feedback control until the beam power is enhanced ultimately. The final experiment illustrates the feasibility of enhanced Raman effects with controlling cavity length and obtaining build-up optical power. The Power Build-Up cavity enhanced Raman spectroscopy has the potential to become a standard method for sensitive gas phase Raman spectroscopy.
Athermalization of infrared dual field optical system based on wavefront coding
Kai Jiang, Bo Jiang, Kai Liu, et al.
Wavefront coding is a technology which combination of the optical design and digital image processing. By inserting a phase mask closed to the pupil plane of the optical system,the wavefront of the system is re-modulated. And the depth of focus is extended consequently. In reality the idea is same as the athermalization theory of infrared optical system. In this paper, an uncooled infrared dual field optical system with effective focal as 38mm/19mm, F number as 1.2 of both focal length, operating wavelength varying from 8μm to 12μm was designed. A cubic phase mask was used at the pupil plane to re-modulate the wavefront. Then the performance of the infrared system was simulated with CODEV as the environment temperature varying from -40℃ to 60℃. MTF curve of the optical system with phase mask are compared with the outcome before using phase mask. The result show that wavefront coding technology can make the system not sensitive to thermal defocus, and then realize the athermal design of the infrared optical system.
Study on general design of dual-DMD based infrared two-band scene simulation system
Yue Pan, Yang Qiao, Xi-ping Xu
Mid-wave infrared(MWIR) and long-wave infrared(LWIR) two-band scene simulation system is a kind of testing equipment that used for infrared two-band imaging seeker. Not only it would be qualified for working waveband, but also realize the essence requests that infrared radiation characteristics should correspond to the real scene. Past single-digital micromirror device (DMD) based infrared scene simulation system does not take the huge difference between targets and background radiation into account, and it cannot realize the separated modulation to two-band light beam. Consequently, single-DMD based infrared scene simulation system cannot accurately express the thermal scene model that upper-computer built, and it is not that practical. To solve the problem, we design a dual-DMD based, dual-channel, co-aperture, compact-structure infrared two-band scene simulation system. The operating principle of the system is introduced in detail, and energy transfer process of the hardware-in-the-loop simulation experiment is analyzed as well. Also, it builds the equation about the signal-to-noise ratio of infrared detector in the seeker, directing the system overall design. The general design scheme of system is given, including the creation of infrared scene model, overall control, optical-mechanical structure design and image registration. By analyzing and comparing the past designs, we discuss the arrangement of optical engine framework in the system. According to the main content of working principle and overall design, we summarize each key techniques in the system.
Design of a common-aperture VIS/LWIR imaging optical system with muti-field of view
Jing Duan, Kai Liu, Gang Li, et al.
In order to achieve the multi-band and multi-field of view imaging for target and to meet the needs of target detection for large amount of information, a common-aperture visible light/long-wave infrared(VIS/LWIR) imaging optical system with muti-field of view was designed. In this paper, the aperture is 400mm, the working wavelength is 500~700nm and 7.5~10μm, the temperature range is -15℃~+50℃, this system can realize 1500mm and 3000mm dual focal length(VIS), the full field of view of short focal length is 1.16° and long focal length is 0.58° respectively, and realize 1400mm focal length(LWIR) and the full field of view of 0.54°, satisfy 100% cold shield efficiency. A re-imaging system was adopted in this designed optical system consists of main optics, VIS projection components and LMIR projection components. First of all, the structural selection and the initial parameter calculation were introduced in detail. Secondly, to improve image quality and environment adaptability, the analysis of temperature change was described particularly and the structural design requirements were put forward according to the analysis of the data. The design results proved that at the spatial frequency of 50 lp/mm, the axis MTF of the VIS system is greater than 0.48, the MTF of the LWIR system approaches the diffraction limit, the system can offer a high resolution and excellent images in whole range of the focal length, and it has the advantages of good adaptability, compact structure and small size, the results satisfy the design requirement.
Host-guest interaction between Acridine orange molecules and AFI or CHA zeolite crystals
Yanping Chen, Ling Fu, Xintong Xu, et al.
Acridine orange (AO) molecules were incorporated in AlPO4-5, SAPO-5 and SAPO-47 single crystals by vapor-phase diffusion method. Polarized absorption spectra show that AO molecules are well aligned by the one-dimensional channel systems of AlPO4-5 and SAPO-5 matrices. While the orientation of AO molecules in SAPO-47 crystals is diverse owing to the three-dimensional cage structure of chabazite (structure code CHA). The absorption peak and emission peak of AO/SAPO-5 blue shift compared with that of AO/AlPO4-5 because the channel environment changes from non-polar medium to polar medium when Si substituted in the framework of AlPO4-5. The greater blue shift in absorption band and emission band of AO/SAPO-47 are expected to originate from the polar channel medium and smaller channel size of SAPO-47.
The development of 4-channel Fourier transform polarization spectrometer
A 4-channel Fourier transform polarization spectrometer is conceptually proposed and experimentally demonstrated as an extension of the conventional Fourier transform spectrometer for scalar spectra collection. The design consists of a typical Michelson interferometer and four sets of polarizer arrays inserted into the incident light path, two interference arms and an output light path, respectively. This novel device facilitates the measurement of all elements in the coherence tensor of a radiative source simultaneously. As an extension of the Wiener-Khintchine theorem, the four sets of spectra with polarization information can be recovered by applying Fourier transforms to the recorded sets of interferograms. The reconstructed polarization spectra have been displayed on a Poincare sphere to demonstrate how a light source emits radiation at each wavelength with different polarization information. The proposed Fourier transform polarization spectrometer provides a new opportunity to identify unknown birefringent materials and determine the quality and content of a birefringent sample for material analysis.
Fourier modal method for two-dimensional wavefront reconstruction
Peiying Liang, Jianping Ding, Jianpei Xia, et al.
This paper introduces a new way of two-dimensional wavefront reconstruction based on the Fourier modal method. Expending the target wavefront by using Fourier series, calculating the expansion coefficient based on the differential phase measured from the experiment, and fitting the coefficients at the missing points by averaging adjacent values, the target wavefront could be reconstructed eventually by using inverse Fourier transform on the expansion coefficients. The paper also introduces our numerical simulation study on the precisions of both the wavefront reconstruction under ideal situation and under the situation with simulated noise respectively. Corresponding verification experiment for the two-dimensional wavefront reconstruction based on the Fourier modal method is also done by using a two-grating lateral shearing interferometry system, with the 3D profile of the sample obtained.
Design to improve photoelectric efficiency for photovoltaic cell array for laser power beaming
Photovoltaic cell (PV) array is a photovoltaic conversion device for laser power beaming, and uneven distribution of laser beam energy will have negative influence on the photovoltaic efficiency of PV array. In order to improve the photovoltaic efficiency under uneven laser irradiation, an optimized and efficient parallel-series PV array is designed. Based on the mathematical model and MATLB/Simulink simulation model of PV array , the influencing factors of photovoltaic efficiency are analyzed, and the concept and scheme to improve the photovoltaic efficiency of parallel-series PV array are proposed. Finally, compared with typical PV array, the effects improving efficiency of optimized array is simulated and analyzed. The simulation results show that under uneven laser irradiation, the optimized parallel-series PV array can obtain higher photovoltaic efficiency.
A vision-based fall detection algorithm of human in indoor environment
Hao Liu, Yongcai Guo
Elderly care becomes more and more prominent in China as the population is aging fast and the number of aging population is large. Falls, as one of the biggest challenges in elderly guardianship system, have a serious impact on both physical health and mental health of the aged. Based on feature descriptors, such as aspect ratio of human silhouette, velocity of mass center, moving distance of head and angle of the ultimate posture, a novel vision-based fall detection method was proposed in this paper. A fast median method of background modeling with three frames was also suggested. Compared with the conventional bounding box and ellipse method, the novel fall detection technique is not only applicable for recognizing the fall behaviors end of lying down but also suitable for detecting the fall behaviors end of kneeling down and sitting down. In addition, numerous experiment results showed that the method had a good performance in recognition accuracy on the premise of not adding the cost of time.
Study on light scattering characterization for polishing surface of optical elements
Yingge Zhang, Ailing Tian, Chunhui Wang, et al.
Based on the principle of bidirectional reflectance distribution function (BRDF), the relationship between the surface roughness and the spatial scattering distribution of the optical elements were studied. First, a series of optical components with different surface roughness was obtained by the traditional polishing processing, and measured by Talysurf CCI 3000. Secondly, the influences of different factors on the scattering characteristics were simulated and analyzed, such as different surface roughness, incident wavelength and incident angle. Finally, the experimental device was built, and the spatial distribution of scattered light was measured with the different conditions, and then the data curve variation was analyzed. It was shown that the experimental method was reliable by comparing the simulation and experimental results. Base on this to know, many studies on light scattering characteristics for optical element polishing surface can try later.
A division-of-wave-front photopolarimeter for the measurement of the polarization state of light
Hongwen Gao, Chunmin Zhang, Yu Wang, et al.
A novel division-of-wave-front photopolarimeter for simultaneously measuring the polarization state of light is described. An incident light beam is divided by a composite beam splitter into four branches which are then detected by four independent detecting units respectively. The measured signal values from the four detecting units are used to form a signal vector. The instrument matrix of the system is obtained by calibration experiment. The Stokes vector describing the polarization state of an incident light is obtained by the matrix calculation by using the signal vector and the instrument matrix. The calculated result for an incident light is in good agreement with the measurement.
A novel experimental mechanics method for measuring the light pressure acting on a solar sail membrane
Aiming Shi, Li Jiang, Earl H. Dowell, et al.
Solar sail is a high potential ‘sailing craft’ for interstellar exploration. The area of the first flight solar sail demonstrator named “IKAROS” is 200 square meters. Future interplanetary missions will require solar sails at least on the order of 10000 square meters (or larger). Due to the limitation of ground facilities, the size of experimental sample should not be large. Furthermore the ground experiments have to be conducted in gravitational field, so the gravity effect must be considered in a ground test. To obtain insight into the solar sail membrane dynamics, a key membrane flutter (or limit cycle oscillations) experiment with light forces acting on it must be done. But one big challenge is calibrating such a tiny light force by as a function of the input power. In this paper, a gravity-based measuring method for light pressure acting on membrane is presented. To explain the experimental principle, an ideal example of a laser beam with expanders and a metal film is studied. Based on calculations, this experimental mechanics method for calibrating light pressure with an accuracy of 0.01 micro-Newton may be realized by making the light force balance the gravity force on the metal films. This gravity-based measuring method could not only be applied to study the dynamics characteristics of solar sail membrane structure with different light forces, but could also be used to determine more accurate light forces/loads acting on solar sail films and hence to enhance the determination of the mechanical properties of the solar sail membrane structure.
Research on key technology in the real-time and high-precision spot centroid detection
Siyu Zhou, Shanshan Wang, Xiaohe Luo, et al.
This paper analyzes the influence on the centroid detection accuracy by several parameters, including the signal-to-noise ratio, frame rate and spot diameter. It provides the selection basis for the camera used in the centroid detection system. The diameter of the spot has little influence on the centroid detection accuracy within a wide range. Meanwhile, with the same signal-to-noise ratio, when the frame rate of the camera becomes higher, the centroid detection accuracy can be improved through the method of superposing more frames. The measurement software uses the specific multi-frame superposition denoising algorithm based on high speed CMOS camera which solves the conflict of improvement of accuracy and time-consuming of the algorithm. The repeatability of the centroid can reach up to 0.0023 pixel with the measuring speed of 62.5fps, the same as the frame rate of the camera.
Study on the optical properties of the off-axis parabolic collimator with eccentric pupil
Gang Li, Xin Gao, Jing Duan, et al.
The off-axis parabolic collimator with eccentric pupil has the advantages of wide spectrum, simple structure, easy assembly and adjustment, high performance price ratio. So, it is widely used for parameters testing and image quality calibration of ground-based and space-based cameras. In addition to the Strehl ratio, resolution, wavefront aberration, modulation transfer function, the general evaluation criteria on the imaging quality of the optical system, the beam parallelism characterize the collimator angle resolving capability and collimation condition of the collimator with the target board, can be measured easily ,quickly and operation process is simple, but the study mainly focus on how to measure it so far. In order to solve Quantitative calculation of this problem, firstly, the discussion of aberration condition of the off- axis parabolic is carried out based on the primary aberration theory. Secondly, analysis on the influencing factor on collimator optical properties is given, including the geometrical aberrations of spherical aberration, coma, astigmatism , the relation between the position of the eccentric pupil and the aberration and optical element surface wavefront aberration, after that, according to the basis of diffraction and wavefront aberration theory, the paper deduced calculation method of the beam parallelism, at last, an example of a 400mm diameter off-axis parabolic collimator with eccentric pupil is given to calculate, the practical results shows that calculation data is well in accordance with actual measurement data and results can meet the demand and has a guiding significance to the actual project manufacture and the theory analysis.
Polarization imaging of an edge object with partially coherent light
Although most scientists and engineers working in the field of image acquisition and processing are well aware of the partially polarized nature of the optical fields used to form images, the effect of coherence on polarization imaging systems seems to have gone largely unnoticed. In this paper, the effects of polarization imaging of an edge object with partially coherent light are investigated theoretically and experimentally. We have extended the use of edge trace analysis in the evaluation of optical system performance and presented theoretical analysis on polarization imaging of an edge object with partially coherent and partially polarized illumination. Some interesting effects, such as the edge ringing and shifting in Stokes vector image construction, have been demonstrated experimentally.
Research on environment correction algorithm in the minimum deviation angle method for refractive index measuring
Chuan Sun, Shanshan Wang, Siyu Zhou, et al.
This paper studies environment correction algorithm in the minimum deviation angle method for refractive index measuring. The principle equation of minimum deviation angle method, based on the refractive index of air and the absolute refractive index of glass specimens is derived. The environmental factors are analyzed which may affect the measurement results in the process of actual measurement. According to thermal characteristics equations of glass, absolute index of refraction of glass for certain material is related to temperature. According to the Edlén equation, refractive index of air is related to temperature, pressure, humidity and so on. Sometimes, the environmental factors are uncontrollable, refractive index will change over the environmental factors, including temperature, pressure and humidity. The correction algorithm of refractive index which modified the measurement results from the non-standard environmental conditions to standard conditions is perfected. It improves the correction accuracy. Taking H-ZK9B for example, the impact of environmental factors on the refractive index is analyzed adopting controlling variable method. The need for environmental factors correction in different accuracy requirements is given. To verify the correction method, two sets of measured refractive index data of the same glass are corrected which measured under different environmental factors. The difference between the two sets of data is less than 1×10-6 with the correction.
Simulation of the fixed optical path difference of near infrared wind imaging interferometer
As an important part of the earth, atmosphere plays a vital role in filtering the solar radiation, adjusting the temperature and organizing the water circulation and keeping human survival. The passive atmospheric wind measurement is based on the imaging interferometer technology and Doppler effect of electromagnetic wave. By using the wind imaging interferometer to get four interferograms of airglow emission lines, the atmospheric wind velocity, temperature, pressure and emission rate can be derived. Exploring the multi-functional and integrated innovation of detecting wind temperature, wind velocity and trace gas has become a research focus in the field. In the present paper, the impact factors of the fixed optical path difference(OPD) of near infrared wind imaging interferometer(NIWII) are analyzed and the optimum value of the fixed optical path difference is simulated, yielding the optimal results of the fixed optical path difference is 20 cm in near infrared wave band (the O2(a1Δg) airglow emission at 1.27 microns). This study aims at providing theoretical basis and technical support for the detection of stratosphere near infrared wind field and giving guidance for the design and development of near infrared wind imaging interferometer.
Methods of degrading the polarization sensitivity of remote sensing cameras for ocean exploration
Xiaoman Li, Jingyi Wang, Feng Zhou
Natural light will be partially polarized or totally polarized after the reflection, scattering, absorption and refraction of the objects. When detecting the ocean from the satellite orbit, the remote sensing signal of water is mainly composed of three parts: radiation signals of atmosphere after photon scattering, the direct reflection of light when the sunlight reaches the surface of the water, and the light after scatting backward. The sunlight will be polarized when it passes the atmosphere. Also, the polarization state of the incident light will be changed when it passes in the water. For remote sensing cameras with quantitative detection application, it is necessary to suppress the polarization sensitivity of the system as far as possible. Through the layout of the optics, the film layer design, the design of the depolarizer, we can achieve low polarization sensitivity.
An estimated method of visibility for a remote sensing system based on LabVIEW and Arduino
Visibility data have long needed to traffic meteorological monitoring and warning system, but visibility data have monitored with expensive special equipment. Visibility degradation in fog is due to the light scattering of fog droplets, which are transit from aerosols via activation. Considering strong correlation between PM2.5 (Particulate matter with diameters less than 2.5μm) mass concentration and visibility, regression models can be useful tools for retrieving visibility data from available PM2.5 data. In this study, PM2.5 is measured by low cost and commercial equipment. The results of experiment indicate that relative humidity is the key factor to impact accuracy correlation between PM2.5 and visibility, the strongest correlation locates in the RH (<60%). Results of the studies suggest that visibility decreases with increases of PM2.5 mass concentration; however, it has been found the decrease rate tapers off gradually. In order to capture the real-time visibility data, to grasp the process of low visibility events, the design of remote monitoring system is put forward. Using the GPRS network to link to cloud as a server, proposed the Arduino as the controller, design and implements a wireless serial acquisition and control system based LabVIEW and Arduino, this system can achieve the function of real-time synchronization Web publishing. The result of the test indicates that this system has typical characteristics of friendly interface, high levels of reliability and expansibility, moreover it can retrieve visibility data from available PM2.5 data that can easy to access by low-cost sensor along the highway.
Review of 1064nm single frequency fiber laser based on different saturable absorber
Pan Fu, Xiaoqiang Feng, Baole Lu, et al.
The current state of single frequency fiber laser technology based on different saturable absorbers (SA) is reviewed. The proposed and experimental fiber lasers used ytterbium-doped fiber (YDF) as the gain medium and the mode selection is done by Sagnac interferometer loop mirror filter (LMF) incorporated SA. In this paper, we review the experiment principle and process of SF fiber lasers utilizing different function materials as the SA, including the fabrication, features of the two-dimensional (2-D) materials (graphene and molybdenum disulfide film) SA. The SA is like a narrowband filter to ensure the longitudinal mode operation. Finally, we systematically analysis and compare the experimental results based on different SA.
Study on the key alignment technology of the catadioptric optical system
Chong Song, Xing Fu, Xi-hong Fu, et al.
Optical system alignment has a great influence on the whole system accuracy. In this paper, the processing of optical system alignment was mainly studied, the processing method of optics on the primary and secondary mirrors, front correction lens group and behind correction lens group with high precision centering lathe and internal focusing telescope. Then using the height indicator complete the system alignment of the primary mirror, secondary mirror, front correction group and behind correction group. Finally, based on the zygo interferometer detect the wavefront information. Using this alignment program for catadioptric optical system, the wavefront aberration of optical system, focal length, modulation transfer function (MTF) and other technical indicators have reached the requirements.
Experimental research for relative radiometric calibration of imaging spectrometer based on Savart plates
The basic principle of tempo-spatially mixed modulated Fourier transform imaging spectrometer (FTIS) based on savart plates is outlined. A calibration method of pixel response non-uniformity of charge-coupled device (CCD) camera in such type of instrument is presented. The method which uses column-flat-fields can avoid the influence of interference fringes. The use of polychromatic calibration source can solve the problem of the slant of the fringes in large optical path difference areas. The procedure of calibration experiment and the algorithm of data processing are detailed described. Two groups of relative radiometric calibration coefficient are obtained through the method of least-square. The original images are corrected by using the coefficients to validate its calibration effect. The results indicated that the method can obviously improve the uniformity of pixels and the vignetting artifacts and defect of the instrument can be well corrected. This study provides a theoretical guidance for study, design, modulation, experiment and engineering of FTIS.
Design of VisSWIR continuous zoom optical system
Mingyang Yang, Hongtao Yang, Rui Qu, et al.
For 640 pixel×512 pixel cooled staring focal plane array detector, a VisSWIR wideband continuous zoom optical system with 7X zoom range is presented based on the pattern of the negative zoom group and compensating lens group. The zoom system provides continuous changed in the field of view from narrow to the wide. The zoom optical system works in the range of 0.4μm~1.7μm, F number is 4, the pixel of the detector is 15μm. It realizes 20mm~140mm continuous zoom with a smooth zoom path and provided high image quality with the whole zoom range, the zoom ratio is 7:1. The modulation transfer function(MTF) for the system is above 0.5 within the whole focal length range at spatial frequency of 34lp/mm and it almost approaches the diffraction limit. RMS value of spot diameter was investigation, the maximum distortion value is less than 5% and the surface type of all lens applied is spherical. Moreover, the cam curve after optimization is given by the optical design software Code V macro. The design results provide that the zoom system has the small size, high resolution, excellent image quality and the smooth cam curve etc.
Research on the influence of the vertical temperature profile on the retrieval of CO2 concentration
The growth of the concentration of CO2 results in the global warming. The atmospheric temperature can impact the intensity and the shape of line of the molecular absorption spectrum of CO2, so that the atmospheric vertical temperature profile changes affect the measured absorption spectrum of CO2 by the satellite. This study focuses on the influence of the vertical temperature profile changes at different latitudes and the discontinuity of the profile in the upper layers of the atmosphere on the accuracy of retrieving CO2 concentration. The simulation results suggested that the error of retrieving CO2 concentration caused by the vertical temperature profile changes in the upper layers was much less than 1%.
Comparison of temporal phase-stepping measurement methods used for wind imaging interferometer
Recently, the upper atmosphere wind field has attracted increasingly attention of the researchers. The history, status and the future of temporal phase-stepping measurement methods used for upper atmosphere measurement(UAM) are introduced. The traditional four intensities method which is field-widened, achromatic, temperature compensation wind imaging is presented comparatively. This paper mainly expounds the principle and method for three arbitrary phase-stepping measurement methods. Analysis and calculation of the wind temperature and velocity are described emphatically. The more terse and precise measurement method has scientific significance and practical value for physical geography, atmospheric science, environment protection, national defense and national economic construction.
Low-power and precise temperature control for high-power CCD assembly
Ming Yang, Changchun Gao, Xinhao Lian, et al.
The imaging quality of the remote sensing camera is directly related to the thermal design of CCD. The cycle average thermal control power required by CCD is 1/3 of the whole remote sensing camera under traditional temperature control solution. with the resolution of the remote sensing camera is increasing. Thermal control of CCD components could be a bottleneck in the thermal control of the camera. According to the temperature control requirements of CCD devices , the temperature control scheme of CCD using semiconductor and phase change heat pipe is proposed for the first time. Simulation analysis and experimental verification are carried out on the key components of the temperature control scheme .based on the simulation analysis and experimental verification of key components, the system simulation model was established ,and the relationship between the phase transition temperature and the area of the radiator is obtained by simulation. System simulation results show that the thermal control scheme can meet the requirements and the temperature of the CCD is between 18℃ and 21.5℃. The radiator area is only 16% of the traditional program. The cycle average power consumption under high temperature condition is only 5% of the traditional scheme. the cycle average power consumption under low temperature condition is only 16% of the traditional scheme. the temperature stability of the CCD during imaging period can be improved one order higher by adjusting the starting strategy of the remote sensing camera to ±0.2℃.
Aspheric surface measurement using capacitive probes
Xin Tao, Daocheng Yuan, Shaobo Li
With the application of aspheres in optical fields, high precision and high efficiency aspheric surface metrology becomes a hot research topic. We describe a novel method of non-contact measurement of aspheric surface with capacitive probe. Taking an eccentric spherical surface as the object of study, the averaging effect of capacitive probe measurement and the influence of tilting the capacitive probe on the measurement results are investigated. By comparing measurement results from simultaneous measurement of the capacitive probe and contact probe of roundness instrument, this paper indicates the feasibility of using capacitive probes to test aspheric surface and proposes the compensation method of measurement error caused by averaging effect and the tilting of the capacitive probe.
Crystal structure and optical properties of a neodymium trifluoroacetate complex for liquid laser
Jiangbo She, Rongzhi Nie, Xin Sun, et al.
The neodymium trifluoroacetate complex was synthesized and characterized by single-crystal X-ray diffraction, elemental and TG analysis, FT-IR spectra, and PL spectra. The optical properties of the liquid medium were studied. From the absorption and luminescence spectra, the Judd-Ofelt parameters of the Nd(CF3COO)3 dissovled in phosphorus oxychloride were obtained. Based on the crystal structure, the effects of crystal field and bond valance properties on three intensity parameters Ωt(t=2,4,6) and emission cross-section were analyzed in detail. The emission cross-section of 4F3/24I11/2 fluorescence transition (3.63×10-20cm2) of the new neodymium compound was higher than those of other Nd(III) complexes and even comparable with some laser glasses
Discuss wave-particle duality of light
In the study of quantum remote sensing, quantum spectral imaging. Since the beginning of 2001, after three stages of basic theory, scientific experiment and key technology research, has made breakthrough progress and innovative results. With the deepening of the research work and needs, some basic theoretical issues and cutting-edge technical problems need to be explored and studied. This paper discusses wave-particle duality of light is one of the important content. In more than and 100 years, wave-particle duality of light as research has made important progress. But the wave-particle duality of light is like what? Wave-particle duality of light like mechanism is what? Has been the most intense debate on the issue of Optics and physicists. In this paper, the author firstly summarizes the wave-particle duality of light development history and present situation of the research study, describes the research ideas of wave-particle duality of light; on this basis, the author puts forward the application of lightstring concept focuses on the wave-particle duality of light phenomenological characteristic geometry shape and movement of the content; describes the wave-particle duality of light like generated string-light effect mechanism. To study the wave-particle duality of light like two, a profound understanding of wave-particle duality of light nature, put forward a new research method.
Design of a handheld infrared imaging device based on uncooled infrared detector
This paper, we introduced the system structure and operation principle of the device, and discussed our solutions for image data acquisition and storage, operating states and modes control and power management in detail. Besides, we proposed a algorithm of pseudo color for thermal image and applied it to the image processing module of the device. The thermal images can be real time displayed in a 1.8 inches TFT-LCD. The device has a compacted structure and can be held easily by one hand. It also has a good imaging performance with low power consumption, thermal sensitivity is less than 150mK. At last, we introduced one of its applications for fault diagnosis in electronic circuits, the test shows that: it’s a good solution for fast fault detection.
Research on the effect of Aerosol to the Inversion of hyperspectral XCO2
Meng Gao, Chunmin Zhang, Yueming Zhou
CO2, the greenhouse gas, is the important one of atmospheric trace gases. The accurate observation of CO2 has great significance for the study of climate warming and global carbon cycle. In this paper, SCIATRAN radiation transfer model is simulated to study the effect of the aerosol parameters to the retrieval precision of XCO2.The absorption band of CO2 at 1.61um and O2-A are selected to analyse the sensitivity of aerosol parameters. The absolute error and relative error about the main aerosol parameters, optical thickness and scattering phase function are analyzed. It provides basis on the effective debugging for the model, plays an important role in the improvement of the precision of XCO2 retrieval.
He-Ne laser employing radio frequency for pumping of gain medium
The performance of radio frequency (RF) exciting He-Ne laser is exposed. This text sets out from power circuit, aiming at providing the pumping of gain medium. In order to study the frequency characteristic of RF excitation in He- Ne laser, the frequency ranging from 300MHz to 700MHz is chose to test the discharge property of active medium. It also obtains the optimal RF frequency (432MHz) through experiment, which is important to the improved design of RF exciting He-Ne laser.
Discussion on method of optical surface roughness measurement
Chunyang Wang, Dongmei Lv, Hongwei Shi, et al.
In recent years, with the development of modern optics and laser technology, modern industry for optical surface roughness measurement precision of the increasingly high demand, real-time, fast and precise measurement of surface roughness has become constant subject of optical components in processing and test. In this paper, the current method of measuring the surface roughness of optical components were described in detail, including light scattering method, interferometric method, speckle method, and optical stylus method. Besides, the principles and characteristics of different methods were introduced respectively.
Method and verification for measuring surface roughness of components by angle resolved scattering method
Chunyang Wang, Ruihao Xin, Hongwei Shi, et al.
This paper introduces the automatic measurement system of laser scattering method based on angular resolution. Discuss the principle of laser in optical element surface scattering, propose the method which use angle resolved scattering (ARS) method to measure surface roughness, at the same time the measurement principle experimental platform is built based on the experimental results after verifying the correctness of the angle resolved scattering method.
Terahertz range profile of the tilted-plate
Yanhui Li, Zhensen Wu, Lu Bai
The range profile is studied first in the microwave band. With the advent of the terahertz radar technology, the range profile is studied from microwave band to the terahertz band, which is the terahertz range profile (TRP). The outstanding feature of TRP is that it can obtain the 3-D shape and the range information of the target by one ultra-short pulse without scanning system. In this paper, terahertz range profile theory and simulation is investigated. Terahertz range profile simulation is studied based on the theory of beam scattering by rough target, pulse wave scattering theory and the radar equation, the calculated formula of range profile is obtained. This equation is, in part, dependent upon the target’s scattering strength which is quantified by its radar cross section. As examples, the range profile simulations are done for tilted-plate. It is indicated that the influence of pulse width, beam parameters, transmit-receive angle and target shape, roughness on the simulation results is also analyzed. This paper is offer theory bases and simulation method for abstraction and identification target feature on terahertz waveband.
Global optimization method based on ray tracing to achieve optimum figure error compensation
Xiaolin Liu, Xuejia Guo, Tianjin Tang
Figure error would degrade the performance of optical system. When predicting the performance and performing system assembly, compensation by clocking of optical components around the optical axis is a conventional but user-dependent method. Commercial optical software cannot optimize this clocking. Meanwhile existing automatic figure-error balancing methods can introduce approximate calculation error and the build process of optimization model is complex and time-consuming. To overcome these limitations, an accurate and automatic global optimization method of figure error balancing is proposed. This method is based on precise ray tracing to calculate the wavefront error, not approximate calculation, under a given elements’ rotation angles combination. The composite wavefront error root-mean-square (RMS) acts as the cost function. Simulated annealing algorithm is used to seek the optimal combination of rotation angles of each optical element. This method can be applied to all rotational symmetric optics. Optimization results show that this method is 49% better than previous approximate analytical method.
Numerical simulation of optical interference for double elliptically polarized beams
Kai You, Jing Liu, Hao Lü, et al.
We investigate the optical interference theory of double elliptically polarized beam (EPB) by using complex electric field amplitude vectors, compared with the real vectors for linearly polarized beam (LPB). Numerical simulations can show the differences between them quantitatively and qualitatively. Through altering parameters of double elliptically polarized beam interference configuration, different interference patterns are obtained. And it demonstrates its application potential in optical interference holographic set-up to fabricate optical micro-structures.
Plasma etching of large-size silicon based microchannel plates
Huan Liu, Linlin Fan, Yaojin Cheng, et al.
Microchannel plates (MCPs) are two-dimensional arrays of microscopic channel electron multipliers as the key component of the image intensifier. In this paper, the plasma etching process of large-size microchannel plates based on silicon is developed. Firstly, the etching of micro groove structure is researched for measure easily. The influences of the process parameters on the etching rate and sidewall verticality, such as oxygen flow, the pressure and the inductively coupled plasma (ICP) power, are studied. The results show the etching rate becomes larger and larger with the increasing of the pressure and ICP power. And the oxygen flow contributes to etching. But the sidewall verticality is worse with increasing oxygen flow. Though parameter experiment, the optimized parameter is got: the pressure 10mTorr, the ICP power 600W, the oxygen flow 6sccm. Using this parameter to etch micro-channel array, the microchannel array of largescale is got with pore 10μm, pitch 5μm, aspect ratio 20:1.
Application of fluorescence spectroscopy and imaging in the detection of a photosensitizer in photodynamic therapy
Photodynamic therapy (PDT) is currently an advanced optical technology in medical applications. However, the application of PDT is limited by the detection of photosensitizers. This work focuses on the application of fluorescence spectroscopy and imaging in the detection of an effective photosenzitizer, hematoporphyrin monomethyl ether (HMME). Optical properties of HMME were measured and analyzed based on its absorption and fluorescence spectra. The production mechanism of its fluorescence emission was analyzed. The detection device for HMME based on fluorescence spectroscopy was designed. Ratiometric method was applied to eliminate the influence of intensity change of excitation sources, fluctuates of excitation sources and photo detectors, and background emissions. The detection limit of this device is 6 μg/L, and it was successfully applied to the diagnosis of the metabolism of HMME in the esophageal cancer cells. To overcome the limitation of the point measurement using fluorescence spectroscopy, a two-dimensional (2D) fluorescence imaging system was established. The algorithm of the 2D fluorescence imaging system is deduced according to the fluorescence ratiometric method using bandpass filters. The method of multiple pixel point addition (MPPA) was used to eliminate fluctuates of signals. Using the method of MPPA, SNR was improved by about 30 times. The detection limit of this imaging system is 1.9 μg/L. Our systems can be used in the detection of porphyrins to improve the PDT effect.
Optical properties of a paramagnetic metalloporphyrin hematoporphyrin monomethyl ether coordinated to divalent manganese metal ion
Huimin Zhao, Lixin Zang, Guixiang Hu, et al.
Metalloporphyrins with paramagnetism are becoming research focus because their potential use in biomedical field as fluorescence probes and the magnetic resonance imaging (MRI) contrast agents. Divalent manganese metal ion (Mn2+) has a half-filled 3d shell with a strong paramagnetic effect. To investigate whether porphyrins coordinated to Mn2+ can serve as multiple functional probes, hematoporphyrin monomethyl ether coordinated to Mn2+ (Mn-HMME) was synthesized and its characterization, MRI enhancement property, luminescence property and photosensitivity were studied. Mn-HMME was characterized by UV-visible spectrum and Fourier transform infrared spectrum. It was found that the number of Q bands in the absorption spectrum of Mn-HMME reduced to two compared to free HMME. From the Fourier transform infrared spectrum of Mn-HMME, the characteristic infrared absorption peak of N-H bond in HMME at 970 cm-1 disappears, but the nitrogen-metal characteristic absorption peaks (1114 cm-1 and 1093 cm-1) were observed. The MRI of Mn-HMME indicates that Mn-HMME has relatively strong MRI enhancement effect. From luminescence spectroscopic analysis, the fluorescence emission of Mn-HMME was weaker than that of free HMME but still detectable. This may be caused by the energy transfer from free HMME to Mn2+. The test of photosensitivity of Mn- HMME denotes that the photosensitivity of Mn-HMME disappears. Our results indicate that Mn-HMME has the potential as a multiple functional probe in both fluorescence imaging and MRI.
Short-wave infrared imaging technology on space optical remote sensing system
Wei Jiang, Qiaolin Huang, Zhanping Zhao, et al.
Recently launched spaceborne remote sensors with short-wave infrared (SWIR) spectrum were introduced. Sketch and benefits of uncooled or thermoelectric (TE) cooling linear InGaAs detector were analyzed. A remote sensing imaging system with visible and SWIR spectrums using CCD and InGaAs detectors in one optical system was modeled and calculated. The application of SWIR spectrum was proposed.
The influence of temperature and pressure on primary mirror surface figure and image quality of the 1.2m colorful Schlieren system
Songbo Xu, Peng Wang, Lei Chen, et al.
In this paper, a colorful schlieren system without any protecting windows was introduced which results in that the 1.2m primary mirror would directly be confronted with the pressure and temperature variation from the wind tunnel test. To achieve a good schlieren image under the wind tunnel test working condition of a wide temperature fluctuation range (-10° to 50°) as well as a pressure (2kPa), a new flexible support method of the primary mirror was strategically designed. A finite element model of the primary mirror combined with its supporting structures was built up to approach the surface figure of the primary mirror under the complex working conditions as gravity, temperature variation, and pressure. The schlieren images due to the change of the primary mirror surface figure were simulated by Light-tools software. It was found that the temperature changing and pressure would lead to the variation of the surface figure of the primary mirror surface figure and therefore, results in the changing of the quality of simulated schlieren images.
Numerical simulation of radiation intensity of a long-endurance UAV exhaust system with 2D nozzle
Zhang-bin Huang, Xiao-xia Li, Yunsong Feng, et al.
Exhaust system is the most important infrared radiation source of a long-endurance UAV and the shape of the nozzle contribute to the infrared radiation characteristics of exhaust system. This paper built a 2-D nozzle and use ANSYS14.5 simulated the temperature filed of the plume. And then, spectral infrared radiation characteristics of the plume were obtained by the single band C-G approximation method. Finally, the infrared radiation intensity distribution of the exhaust system of the 2-D nozzle in different planes is obtained. The results show: The infrared radiation of the plume in wide side detection surface is far greater than the narrow side; The infrared radiation of the nozzle in wide side detection surface is smaller than the narrow side; The infrared radiation of the exhaust system in wide side detection surface is smaller than the narrow side. The results maybe contribute to the further study of the infrared radiation characteristics of the long-endurance UAV.
Photonic generation of frequency quadrupling signal for millimeter-wave communication utilizing three parallel Mach-Zehnder modulators
Hang Mu, Yanjun Liu, Daobin Wang, et al.
In this work, we propose a new scheme of generating high quality frequency quadrupling signal for millimeter-wave wireless communication system. The frequency quadrupling scheme is achieved by using three parallel Mach-Zehnder modulators (MZMs) and an optical phase shifter. The first two MZMs are driven by the RF signals to operate at the maximum transmission point. The third MZM is operated with no RF signal and an extra π-phase difference is introduced for it by the optical phase shifter. The advantage of the proposed scheme is that the optical carrier and the fourth optical sideband can be suppressed simultaneously. The performance of proposed scheme is investigated theoretically and evaluated by simulations. Numerical results show that the radio frequency spurious suppression ratio (RFSSR) higher than 44.18 dB and the optical sideband suppression ratio (OSSR) higher than 21 dB can be obtained without optical filter when the extinction ratio (ER) of the MZM is 30 dB. The impact of the non-ideal RF driven voltage and phase difference of RF driven signal applied to the first two sub-MZMs on OSSR and RFSSR is also discussed and analyzed.
A polyatomic photonic crystal ring resonator and its application to the optical biochemical sensor
Yanjun Liu, Hang Mu, Daobin Wang, et al.
In this work, we propose a schematic design for the biochemical sensor, which is based on the polyatomic photonic crystal ring resonator (PCRR). Unlike with the conventional approach, the proposed PCRR is constituted by two different branching waveguides (WG), which are all in the same lattice direction but have different optical propagation properties due to the binary nature of the diatomic square lattice. Electromagnetic analysis via PWE and FDTD numerical techniques are employed to investigate the sensing performance and the results show that the proposed sensor can efficiently detect the small changes in the refractive index of sensing area.
Simultaneous measurement of temperature and strain based on a fiber Bragg grating with cladding made of electro-optic crystal material
Hang Fan, Yanjun Liu, Daobin Wang, et al.
In this paper, a novel fiber Bragg grating (FBG) sensor which can measure the temperature and strain simultaneously is presented. The cladding layer of the proposed FBG sensor is made of a uniaxial crystal material (LiTaO3) and the electric field is applied on the 1/2 area of the sensor. The sensing performance was investigated by the coupled-mode theory and dual-wavelength method. We found that the strain sensitivity and the temperature sensitivity of the 1/2 area with no electric field are 0.841 pm/με and 14.31 pm/°C respectively. If the electric field is increased from 0 to 400×107 v/m, the temperature sensitivity of this device varies from 14.31 pm/°C to 14.12 pm/°C and its strain sensitivity varies from 0.841 pm/με to 0.850 pm/με. So, the obtained results demonstrate that the simultaneous measurement of temperature and strain can be achieved by using this scheme. The proposed sensor has potential applications in optical fiber sensing systems due to small size, high sensitivity and compatible with optical fiber.
Study of the fusion point between PM-PCF and panda fiber and its influence to Interferometric fiber-optical gyroscope
Zuoming Sun, Shuhua Wang, Junwei Li
Microhole collapse property of polarization maintaining photonic crystal fibers (PM-PCF) and its effect on the splice loss and polarization cross-coupling during fusion splicing were investigated. The relationship between the microhole collapse and polarization cross-coupling are analyzed through simulation and experiment. Finally their influence to the phase error of the FOG is calculated and tested.
Numerical study of the light output intensity of the bilayer organic light-emitting diodes
The structure of organic light-emitting diodes (OLEDs) is one of most important issues that influence the light output intensity (LOI) of OLEDs. In this paper, based on a simple but accurate optical model, the influences of hole and electron transport layer thickness on the LOI of bilayer OLEDs, which with N,N0- bis(naphthalen-1-yl)-N,N0- bis(phenyl)- benzidine (NPB) or N,N′- diphenyl-N,N′-bis(3-methylphenyl)-1,1′-biphenyl-4,4-diamine (TPD) as hole transport layer, with tris(8-hydroxyquinoline) aluminum (Alq3) as electron transport and light emitting layers, were investigated. The laws of LOI for OLEDs under different organic layer thickness values were obtained. The results show that the LOI of devices varies in accordance with damped cosine or sine function as the increasing of organic layer thickness, and the results show that the bilayer OLEDs with the structure of Glass/ITO/NPB (55 nm)/Alq3 (75 nm)/Al and Glass/ITO/TPB (60 nm)/Alq3 (75 nm)/Al have most largest LOI. When the thickness of Alq3 is less than 105 nm, the OLEDs with TPD as hole transport layer have larger LOI than that with NPB as hole transport layer. The results obtained in this paper can present an in-depth understanding of the working mechanism of OLEDs and help ones fabricate high efficiency OLEDs.
A combination of JND curve property and intensity-pair distribution for image enhancement
Bin Zou, Yang Lu, Jun Qian, et al.
In recent years, the distribution characteristic of pixel intensity-pairs is proposed, which effectively absorbing the advantages of global and local image enhancement algorithms, avoiding over enhancement, noise amplification and other defects. However, the performance of the algorithm is heavily dependent on the selection of local artificial thresholds. In this paper, by the Just Noticeable Difference(JND) curve from human visual system, dynamic thresholds with visual sense are generated. Then image pixels are divided into different channels for statistical processing, in order to construct mapping functions. Finally, the enhanced image is a weighted fusion of different channels. The experiment results show that the proposed algorithm has better effect and adaptability.
ZnS:Co film grown by pulsed laser deposition and optical properties analysis
Dongwen Gao, Li Wang, Shufeng Li
The modification of ZnS by doping method is one of the important directions in the research of ZnS nano materials. Doping of transition metal ions in the ZnS matrix has attracted much attention in recent years. Doping transition metal ions can modulate the emission region of ZnS, and improve the efficiency of fluorescence. The doping concentration in ZnS has determined the distribution, absorption, excitation, emission, and structural properties of particles. Due to ZnS:Co crystal materials have the best characteristics: the stability of the mechanical properties, high emission cross section and wide bandgap tuning at room temperature. So the ZnS:Co film is grown by pulsed laser deposition and the near infrared spectrum properties have analyzed that have researched in theory and experiment. We change the pressure in the vacuum chamber by controlling the pressure of the argon gas to fabricated the ZnS:Co film by PLD, at the same time, we chose three kinds of materials as the substrate of the thin film, and compared the characteristics of the thin films. This method has the advantages of short fabrication time and material saving, so it is good for to detect and research the optical properties of the films of ZnS:Co. A variety of film detection of X-ray diffraction, laser particle size analyzer, UV-Vis spectrophotometer, fluorescence spectrophotometer, morphology, the particle size and optical properties of the samples have tested. From the results, the infrared transmittance of the Co doped ZnS is almost above 90%, and the transmission capacity increases with the increase of pressure. The film thickness decreases with the increase of pressure and there is a sharp peak in absorption spectrum, this point has important significance for studying photoluminescence of the near infrared spectrum.
Operational data quality evaluation based on BP neural network and rough set theory
It analyzed the factors affecting the Operational Data Quality, determined the evaluation index system, set up Operational Data Quality evaluation element and evaluating network, established the six-element evaluation model. Using Rough Set theory come to realize information reduction and using BP Neural Network theory come to realize quality evaluation. This method could enhance the scientificity and objectivity of evaluation. The results showed that the evaluation method of error was small, simple and practical.
Programmable spectral engine design of hyperspectral image projectors based on digital micro-mirror device (DMD)
Recently, hyperspectral image projectors (HIP) have been developed in the field of remote sensing. For the advanced performance of system-level validation, target detection and hyperspectral image calibration, HIP has great possibility of development in military, medicine, commercial and so on. HIP is based on the digital micro-mirror device (DMD) and projection technology, which is capable to project arbitrary programmable spectra (controlled by PC) into the each pixel of the IUT1 (instrument under test), such that the projected image could simulate realistic scenes that hyperspectral image could be measured during its use and enable system-level performance testing and validation. In this paper, we built a visible hyperspectral image projector also called the visible target simulator with double DMDs, which the first DMD is used to product the selected monochromatic light from the wavelength of 410 to 720 um, and the light come to the other one. Then we use computer to load image of realistic scenes to the second DMD, so that the target condition and background could be project by the second DMD with the selected monochromatic light. The target condition can be simulated and the experiment could be controlled and repeated in the lab, making the detector instrument could be tested in the lab. For the moment, we make the focus on the spectral engine design include the optical system, research of DMD programmable spectrum and the spectral resolution of the selected spectrum. The detail is shown.
Study of femtosecond laser spectrally resolved interferometry distance measurement based on excess fraction method
Rongyi Ji, Kun Hu, Yao Li, et al.
Spectrally resolved interferometry (SRI) technology is a high precision laser interferometry technology, whose short non-ambiguity range (NAR) increases the precision requirement of pre-measurement in absolute distance measurement. In order to improve NAR of femtosecond laser SRI, the factors affecting NAR are studied in measurement system, and synthetic NAR method is presented based on excess fraction method to solve this question. A theoretical analysis is implemented and two Fabry-Perot Etalons with different free spectral range are selected to carry out digital simulation experiments. The experiment shows that NAR can be improved using synthetic NAR method and the precision is the same with that of fundamental femtosecond laser SRI.
Theoretical and experimental investigation on superconducting nanowire single-photon detectors
Single-photon detectors have been widely used in many vital fields, such as quantum teleportation and quantum computation. Compared with other single-photon detectors, superconducting nanowire single-photon detector exhibits relatively wide response spectrum, low dark count rate and high detection efficiency. The principle of superconducting nanowire single-photon detector is demonstrated, especially on the process of the generation and the diffusion of the hotspot, and the simulation is done to illustrate this process. Many important parameters of superconducting nanowire single-photon detector are measured, such as R-T curve and photon response. Through the analysis of experimental data, the approach to improve the performance of superconducting nanowire single-photon detector is proposed.
System design for adopting magnetofluid and LPFG to measure magnetic field and temperature
Jie Zhang, Hai-bo Ge, Hao Cheng, et al.
Owing to the insufficient attention to temperature change resulting from the magnetic field sensing scheme of magnetic liquid and long period fiber grating (LPFG), the sensing scheme that measures magnetic field and also the temperature at the same time by using magnetic liquid and two cladding long period fiber gratings with different effective thermal optical coefficient is presented. By measuring the difference of resonance wavelengths between the two long period fiber gratings, the variation of temperature is obtained and then the magnetic field measurement results will be corrected. The relationship between a certain range of temperature variation and the variation of resonance wavelength of long period fiber grating and the magnetic liquid refractive index will be revealed by means of theoretical analysis. System emulation indicates that if the ambient temperature variation is within 14 °C, the maximum relative error of obtained temperature is 1.5% and the precision of magnetic field intensity based on the magnetic field sensing scheme of magnetic liquid and long period fiber grating is at least improved by 70%.
Design of edge filter demodulation system based on twin-core LPFG
Peiwen Wei, Haibo Ge, Yong Yang
By using the linearity of the edge filter in a specific wavelength range of twin-core long period fiber grating(LPFG), a new method for measuring the strain of the fiber grating with high-precision and wide range measurement is proposed. Namely, proceeding from the demodulation principle of twin-core LPFG transmission spectrum and fiber Bragg grating(FBG) reflection spectrum, we designed a kind of high-precision twin-core LPFG demodulation system to demodulate strain sensing signal, which is based on the measurement of light intensity, and it is applicable to the static and dynamic measurement. And through the theoretical calculation and system simulation, the strain sensing signal can be achieved a 10nm range of linear demodulation, and the positive and negative strain can be detected, the linear fitting degree reached 99.58%, which is of good practical value.
Research on alignment between processing and testing coordinates in flat mirror manufactory
Lisong Yan, Qiang Li, Yaotao Shi, et al.
To accomplish the alignment between processing and testing coordinates in the manufacturing of SiC flat mirror, which can be used to assure the acquisition of final surface, we established a kind of model based on least square method. With actual project, we achieved the alignment of two coordinates in the manufacturing of a φ800mm flat mirror. The surface reached the final accuracy with this alignment model, which verified the accuracy and reliability of this alignment model.
Study and analysis on slow light in photonic crystal waveguide
Shuzhen Dang, Jing Shu
Slow light is to reduce the light propagation speed in the medium. In recent years, because slow light technology is the key to achieving all-optical network technologies constitute optics, it attracted people's attention. Compared with other methods, photonic crystal waveguides provide slow light with many adventages, especially we can fine tune the structure to control the performance of the slow-light. Because the two-dimensional triangular lattice photonic crystal is easier to form band gaps than two-dimensional cubic lattice photonic crystal, the circular dielectric rod is easier to form band gaps than square dielectric cylinder, when the photonic crystal lattice vector angle is greater than 60 degrees, it can make the performance of slow light more excellent. So in this paper,we will rotate the cubic lattice 45 degrees counterclockwise. By reducing the radius of middle row of medium column to form the line defect; Additionly, we design a coupled cavity waveguide. Using the plane wave expansion method (PWE), we have analyzed the dispersion curves of the guided mode, the corresponding group refractive index and group velocity dispersion of slow light. For the line defected waveguide, we have realized the group refractive index changing from 8.1 to 84.8 by fine tuning the radius of the defective rod, the position and radius of the first row of the dielectric cylinder close to the waveguide. For the coupled cavity waveguide, we have realized the group refractive index changing from 16 to 79 by fine tuning the radius of the defective rod.
Effect of polarizer parameters on measuring Verdet constant of magneto-optical glass
The traditional measurement for Verdet constant of magneto-optic glass is to measure the Faraday rotation angle indirectly by using optical power meter, which is based on the Faraday rotation effect. There is a relatively large measurement error, because the method neglects the influence of the extinction ratio of polarizer and the axis angle. In our research, a method based on Jones matrix and simulation is studied and used to improve the measurement accuracy. The extinction ratio of polarizer and the axis angle are discussed during the measurement. The experiment system is built for measuring the Verdet constants of ZF7 glass and Ce3+/Tb3+ co-doped glass, by using the He-Ne laser light source, and different polarizers. The results show that the changes of the polarizer’s extinction ratio mainly affected the Verdet constant measurement. The lower extinction ratio, the larger measurement error. The extinction ratio more than 1:1000 for the polarizer is necessary for an accurate measurement, which has important value in terms of reference and guidance for the accurate measurement of Verdet constant of magneto optic glass.
Simulation and design of solar-blind Raman Lidar for water vapor measurement
Dongchen Shi, Dengxin Hua, Fei Gao, et al.
A novel water vapor Raman Lidar is developed at a solar-blind wavelength of 266nm. To obtain signals of Mie-Rayleigh scattering spectra and Raman scattering spectra of H2O, N2 and O2 with fine separation and high efficient extraction, a newly high-efficiency Raman polychromatic system is designed using the combination of dichroic mirrors and narrow– band interference filters. Using the standard atmospheric scattering models and aerosol extinction coefficients, the rejection rate of Mie-Rayleigh scattering signals and the signal-to-noise ratio of atmospheric water vapor measurement are simulated. The optimal parameters of Lidar system are obtained based on the detailed analysis and the discussion of the SNR of echo signals. Lidar emission wavelength and Raman scattering echo wavelengths are all in the ultraviolet range below 300nm known as the “solar-blind” region, because practically all radiation at these wavelengths is absorbed by the ozone layer in the stratosphere. It has the advantage of detecting water vapor in the daytime without the influence of solar background radiation in the system. Through the comparison between the Raman Lidars at the wavelengths of 266nm and 355nm respectively, it is concluded that the detection performance of the designed system at 266nm is better than the Raman Lidar system at 355nm during the daytime measurement, and the measurement height can be up to the 4 km.
Infrared scene projector optical system design with wide field-of-view
Yang Qiao, Xinyang Xu, Yue Pan, et al.
Infrared scene projector is essential and standard equipment for training and testing IR threat detection systems including missile warning systems and hostile fire indicators. DMD as one of the scene generator used in IRSP has performed several attractive features including high spatial resolution, high framerates, no dead pixel and excellent uniformity. In this paper we proposed a new structure of DMD based IRSP. We use a field lens and a mirror as separator to achieve a wide field-of-view optical system design. Since the field lens is a part of the illumination path as well as projection path, it brings several challenges to the optical system design. In this approach we detailed analyze the design method and perform test equipment and facilities we developed.
Polarization insensitive and low-loss coupling mode-size converter from super luminescent diode to silica-based planar lightwave circuit
We present a design of a laterally tapered optical waveguide mode-size converter from super luminescent diode (SLD) to silica-based planar lightwave circuit (PLC). The mode-size converter is based on silica-based PLC. By using three dimensional semi-vectorial beam propagation methods, laterally tapered waveguides with different boundaries are simulated and compared with each other, where the factors of polarization-dependent loss and coupling loss are mainly focused on. The results show that the most influential factor for polarization-dependent loss is the ratio of the divergence angle of SLD in the horizontal direction and the vertical direction. The refractive index difference Δ between core layer and cladding layer, core width of endface and taper length influence coupling loss mostly, while the effect of all side boundaries is within 0.05 dB. We also investigate the SLD misalignment tolerance and wavelength bandwidth’s impact on coupling loss. Furthermore, we examine the performance of the mode-size converter based on a particular SLD which has a divergence angle of 30°×45°. By optimizing the parameters of the tapered waveguide, the coupling efficiency is increased to 62.4% and the polarization-dependent loss is reduced to 0.035 dB. Meanwhile, it eΔnables us to reduce the coupling loss variation to 0.05dB with core width of endface fabrication tolerance of ±0.5 μm and taper length tolerance of ±0.5 mm. The proposed mode-size converter has been demonstrated to be well performed, implying its application in the optical transceiver module using SLD as light source and hybrid integration of III–V semiconductor waveguiding devices and PLCs.