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- Poster Session: Solid State Lighting and Display Technologies
- Holography, Speckle Pattern, Interferometry and Applications I
- Holography, Speckle Pattern, Interferometry and Applications II
- Poster Session: Holography, Speckle Pattern, Interferometry and Application
- Micro/Nano Manufacturing and Metrology I
- Micro/Nano Manufacturing and Metrology II
- Micro/Nano Manufacturing and Metrology III
- Poster Session: Micro/Nano Manufacturing and Metrology
Poster Session: Solid State Lighting and Display Technologies
Accelerated aging test on LEDs life estimation
Yi Dong,
Shu-sheng Zhang,
Jiang-qi Du
Show abstract
Light-emitting diodes(LEDs) have become very attractive in different application field such as Solid State Lighting,
automotive and street lights, due to their long operative lifetime, lower energy consumption etc. This paper mainly
introduces the accelerated aging test, we focus our attention on the study of a life model for LEDs by relating the time to
failure with the supplying condition. The constant accelerated aging experiments were firstly performed on LED
samples. Process the experiment data by exploiting the degradation of LED optical power formula and degradation
coefficient. Finally, the average lifetime of the samples under normal conditions was calculated via using numerical
analytical method. According to data, analysis the test result and the failure mechanism of LED, provide the technical
basis to improve product design and quality assurance.
A new type of stereoscopic 3D mini-projector
Show abstract
Mini-projectors based on LED illumination have already become a hotspot of projector industry, and time-sequential
stereoscopic mini-projector has been developed. However, viewers to this type of 3D projector usually suffered from
dark and flickering images caused by false synchronization of images and glasses, and the low transmittance of LC
glasses. We propose a new type of polarized mini-3D-projector, which employs double LED illumination engines, and
double LCoS panels. The optical model of the optical engine for the mini-3D-projector is built based on the measured
optical qualities of the key optical elements. The large divergence angle is the main factor which affects disparity
according to the simulated analysis. The first version of prototype is developed, which has low disparity (<5%) and
performs comfortable viewing experience. This new type of 3D mini-projector has the advantages of the both
conventional 3D projection technologies.
Luminescence properties of Eu2+/Dy3+ co-doped high silica glass for white LED
Show abstract
The Eu2+ and Dy3+ co-doped luminescence high silica glass was prepared by combining porous
glass preparation and sintering process. The emission spectra and excitation spectra of luminescence
glasses were measured. With the excitation of ultraviolet (UV) wavelength of 365nm, there were two
emission bands with central wavelength 480nm and 573nm in spectra of samples which presented the
near white light luminescence. The energy transfer process from
Dy3+ to Eu2+ and concentration quench
process of Eu2+ in samples were demonstrated by comparing the relative spectral intensity of emission
spectra and excitation spectra. This type of glass might be an adoptable candidate for white LED
through an appropriate UV chip excitation.
Holography, Speckle Pattern, Interferometry and Applications I
Comparison and analysis on the methods of improving the image quality in digital hologram reconstruction
Jiansu Li,
Zhao Wang,
Jianmin Gao
Show abstract
Frequency filtering, high pass filtering pro-process method, Laplace differential template, finite impulse response
filtering, and wavelet transform have been proposed for eliminating zero-order diffraction in digital hologram
reconstruction. The characteristics and limitations of these methods are summed up in this paper after systematically
analyzing those. Furthermore, through comparing the quality of reconstructed images with or without a mean filter, it
shows that the contrast and resolution have significantly been enhanced with mean filter. Finally, an effective method of
improving the quality of reconstructed image, which combines wavelet transform with mean filter, is presented by
contrasting and analyzing the experiment results.
Accuracy of a multiple height-transfer interferometric technique for absolute distance metrology
Show abstract
A multiple height-transfer interferometric technique was developed to increase the absolute distance measurement
capability of a metrology system that uses a tunable laser. Using multiple accurately calibrated reference heights, this
technique relaxes the requirement of knowing accurate wavelength information for multiple wavelength interferometry
while maintaining its advantages. We present an uncertainty analysis, analyze the primary sources of uncertainties
limiting the performance of this technique and discuss how errors can be minimized. Measurement results of 3D-images
obtained from a variety of objects are presented. The measurement uncertainty is experimentally demonstrated to be
smaller than 0.2 μm over 50 mm for two discontinuous surfaces.
Three-dimensional information encryption with optical asymmetric cryptography and digital interferometry
Show abstract
An encoding algorithm is proposed for three-dimensional (3-D) information using optical asymmetric cryptosystem and
the digital interferometry. 3-D information can be treated as an ensemble composed of multiple points, and every point
spreads in a spatial limited field. Due to the free space coordinates, the encryption system of 3-D information can be
regarded as an optical asymmetric cryptosystem. We encrypt 3-D information with the double random phase-truncated
encoding, and then record the amplitude of ciphertext by digital interferometry. Computer simulations demonstrate the
feasibility and effective of the proposed method. This cryptosystem is also numerically tested with the incorrect keys, the
addition noise to the ciphertext, and spatial information occluded ciphertext. The proposed algorithm has three
advantages: the high efficiency of encryption, the safety provided by one added dimension, the increasing information
quantity and the optical asymmetric cryptosystems. The high robustness to the system is also achieved.
Holography, Speckle Pattern, Interferometry and Applications II
A location quantization algorithm for three-dimensional information display by using pure-phase computer-generated hologram
Tuo Li,
Ran He,
Yuhua Yang,
et al.
Show abstract
We propose an efficient calculation method to display three-dimensional information with purephase
computer-generated holograms (CGHs). The object composed of points is conventionally
divided into a set of planar segments vertically along with the axis. In this way, the number of planar
segments is less than the number of points, which means that the total number of diffractions needed
to calculate decreases. However, it is low efficient, for sometimes one planar segment only contains
one point. We propose to quantize the locations of planar segments to solve this problem. The
simplest way to quantize locations is to divide the object into the equal interval planar segments
parallel with each other in the axis. The points out of these planar segments are projected to their
nearest segments. Compared to traditional CGHs, the proposed method dramatically reduces the
computing cost. Both simulations and experiments demonstrate the feasibility of the location
quantization algorithm.
The application of DOE in uniform illumination for large area digital speckle pattern interferometry
Show abstract
Uniform illumination plays an important role in Digital Speckle Pattern Interferometry (DSPI) of measuring a large
object. This paper presents a method that by designing a specified DOE with certain algorithm in front of laser diodes, a
large and uniform illumination could be achieved at the designed distance. The fluctuation of no more than 10% has been
analyzed for its influence on interferogram. Only 6 semiconductor lasers are necessary in the interferometer to lighting
its view in theory and the experiment with the simulated illumination has been done. The fringes of deformation at
different parts of the object show that this method is suitable for large area detection.
Robust digital speckle photography based on radon and Fourier-Mellin transforms
Show abstract
We present a new and robust method for determining in-plane displacements of an object from distorted Digital
Speckle Photography (DSP) images. This new approach is designed particularly to facilitate accurate measurement
of deformations of steel samples during a gas quenching heat treatment process, where rigid body motion
and large deformations lead to unwanted image distortions. The new method allows the computation and correction
of image rotation and magnification via Radon and Fourier-Mellin Transformations prior to calculations
of in-plane displacements, thereby alleviating the inaccuracy that arises from the cross correlation of distorted
images in conventional DSP. The method is validated through simulation and measurements with predefined
deformations. Initial studies show that the new method is well suited for this application and that it enables
measurement of displacements with high accuracy in the micrometer range.
Poster Session: Holography, Speckle Pattern, Interferometry and Application
Study of nanometer-level precise phase-shift system used in electronic speckle shearography and phase-shift pattern interferometry
Chao Jing,
Zhongling Liu,
Ge Zhou,
et al.
Show abstract
The nanometer-level precise phase-shift system is designed to realize the phase-shift interferometry in
electronic speckle shearography pattern interferometry. The PZT is used as driving component of phase-shift
system and translation component of flexure hinge is developed to realize micro displacement of non-friction
and non-clearance. Closed-loop control system is designed for high-precision micro displacement, in which
embedded digital control system is developed for completing control algorithm and capacitive sensor is used as
feedback part for measuring micro displacement in real time. Dynamic model and control model of the
nanometer-level precise phase-shift system is analyzed, and high-precision micro displacement is realized with
digital PID control algorithm on this basis. It is proved with experiments that the location precision of the
precise phase-shift system to step signal of displacement is less than 2nm and the location precision to
continuous signal of displacement is less than 5nm, which is satisfied with the request of the electronic speckle
shearography and phase-shift pattern interferometry. The stripe images of four-step phase-shift interferometry
and the final phase distributed image correlated with distortion of objects are listed in this paper to prove the
validity of nanometer-level precise phase-shift system.
Design and manufacture of transmission volume phase holographic grating used in VIS/NIR wave band
Chunhuan Fang,
Minxue Tang,
Jianhong Wu
Show abstract
Due to its uniform dispersion and higher diffraction efficiency, transmission volume phase holographic grating (VPHG)
has been widely used for astronomical spectroscopy, ultrafast lasers compressors and wavelength division multiplexers.
According to its application requirement and based on the Rigorous Coupled Wave Analysis (RCWA), a transmission
VPHG with a frequency of 196lp/mm is designed and manufactured in this paper. The thickness of gelatin and the
modulation of refraction index are optimized for high diffraction efficiency over a wavelength range from 420nm to
1000nm. The grating was recorded in dichromate gelatin (DCG) and in a symmetrical light path. By controlling the coating,
exposure and post-processing conditions, the thickness of gelatin and the modulation of refraction index can be adjusted.
The diffraction efficiency varied within the required wave band and the polarization property of the illumination wave
were measured and compared with that of the theoretical ones. From the results, it can be seen that by adjusting and
controlling the preparation conditions of DCG plates, the exposure value and post-processing technique, the peak
diffraction efficiency of VPHG reaches to 47% and the average diffraction efficiency is above 35% in the spectral
coverage, which is close to the theoretical values. This transmission VPHG can be applied in a prism-grating-prism (PGP)
imaging spectrometer.
Laser holographic projection based on interference
Show abstract
In this paper, a novel method for holographic projection is presented. SLMs are employed to modulate incident light
beams and reconstruct the output image by interference. There is a great advantage of this novel method that the
algorithm for calculation the phase patterns on SLMs does not need iterative process, which is greatly computationally
efficient and hence provides a possibility to achieve real-time video holographic projection based on standard PC
hardware. Two holographic-projection architectures for this novel method are proposed. Simulation results demonstrate
the validity of this new proposed method. It is believed that this technique is useful in further real-time video holographic
projection.
Micro/Nano Manufacturing and Metrology I
The numerical calculation and analysis for designing a polarization beam splitter based on a rectangular phase grating
Hua Gao,
Peng Dong,
Zhiyuan Zheng,
et al.
Show abstract
A new method based on the combination of Finite-Difference
Time-Domain (FDTD) algorithm and Fourier transform was proposed to analyze
the Fraunhofer vector diffraction of gratings in this paper. The interaction of a
grating with the incident linearly polarized light was simulated using FDTD
algorithm, the complex amplitude distribution on the rear plane of the grating
was extracted, and then the Fraunhofer diffraction pattern was obtained by
performing Fourier transform of the complex amplitude. It was found that for the
rectangular phase grating if the period of the grating is comparable to the
wavelength of the incident wave, the propagation speeds of the TE and TM
waves in the dielectric of the grating are different, which makes the diffraction
of the grating is polarization dependent. Besides, the relative phase retardations
of TE and TM waves formed on the rear plane of the grating are different and
both of them can be controlled by changing the thickness of the grating, which
makes it be realized that the intensities of TE and TM waves concentrate onto
the 0th order and 1st order separately by selecting a suitable grating thickness.
Therefore a polarization beam splitter based on a rectangular dielectric grating
can be easily designed.
Studies of the super-smooth mirror roughness by grazing incidence x-ray scattering method
Wei-Tao Du,
Jie Wang
Show abstract
The surface roughness of a large-size super-smooth mirror is studied by grazing incidence X-ray scattering method
(GIXRS). We derive the two-dimensional theoretical model based on Tong's result in 1993; In light of our formulae, the
power spectrum density (PSD) of a mirror surface can be correlated to the intensity distribution of X-ray scattering. A
210mm-long mirror is measured at the beamline 16B at Shanghai Synchrotron Radiation Facility (SSRF) and the data is
analyzed. The result indicates that the root mean square (RMS) of the surface roughness calculated by our formulae is in
good agreement with that measured by a white-light 3D profiler.
A novel in-situ measuring technique for aspheric surface
Show abstract
In this paper, a novel in-situ surface measuring technique for optical elements with aspheric surface is presented. It is a
contact type probe, and can be used for measuring ground surfaces. The theory of this technique develops from
coordinate measuring machine (CMM), and the measurement accuracy of this technique is depended on the accuracy of
computer numerical controlled (CNC). By installing a special equipment with high accuracy measuring head in main
spindle of CNC machine, and moving the probe along the path which is described by a mathematical aspheric expression
precisely, we could get relative errors of sag height of any position in this path. With this technique, the repeat
positioning error caused by traditional off-line measurement will be avoided. The author also has finished a special
software with VC++ 6.0. With this software, the form error of ground work piece could be corrected rapidly. This
software can calculate and handle the arrangement automatically with all parameters which are required to input in
operation interface. In the correction stage, the software can analyze and process error data and generate a new NC
program with corrected data for next grinding stage. After 2 or 3 times measuring and correction, the surface shape error
of the aspheric optical element will be less than 1μm. The finished work piece has a very good surface finish and can be
polished with high quality.
A novel method to calibrate fiber optical tweezers
Peibo Liang,
He Gao,
Lei Wang,
et al.
Show abstract
We present a novel method to calibrate fiber optical tweezers. This paper proposed a new calibrating method solving the
problem, which makes the calibration for fiber optical tweezers in a wide range of output optical field possibly. Based on
electromagnetic field momentum conservation law and
finite-difference time-domain method, we calculated and
analyzed the force of multiple particles are simultaneously trapped, and get the f-x (trapping fore-distance from the fiber
tip) curve, which is consistent to the experimental results. Theoretical and experimental results show that the fiber optical
tweezers is more conducive to study the precise mechanical properties of biological cells in a larger range.
Micro/Nano Manufacturing and Metrology II
Research on motion generation for machining axisymmetric aspheric convex surface
Show abstract
The positions and orientations of the tool and workpiece are analyzed for machining axisymmetric aspheric convex
surface and the position and orientation matrixes of the workpiece and the tool are obtained. The relationship between
the tool and the workpiece is set up by using the method of coordinate transformation. The basic modules and the
necessary motions for generating axisymmetric aspheric convex surface are clarified. And the possible structural
configurations of the machine tool are proposed and optimized. The results in this paper facilitate the innovation design
of a machine tool for generating axisymmetric aspheric convex surface.
Theoretical analysis of optical properties of regular and flexible surface microstructured silicon
Show abstract
In this paper, we study the regular and flexible microstructured silicon theoretically using the Rigorous Coupled
Wave Analysis and Finite Difference Time Domain methods. We calculate the reflective spectra of the conical structures
of three different sizes by using the multi-step approximation. The calculated results show that the smallest 0.5μm
structures have the lowest reflectance. The angle dependence of the reflectance of microstructured silicon is also talked
about. Then the Finite Difference Time Domain method is used to simulate the absorptance of the regular and flexible
microstructured silicon of three different sizes. The simulated results show that the absorptance of flexible
microstructured silicon is a little lower than that of the regular microstructured silicon. At last, The absorption spectrum
of the flexible surface microstructured silicon is as high as 97% in the visible and insensitive to the change of the
incident angle of the light. The calculated results are verified by the measured spectra.
The simulation research of multi-core optical fiber near-field optical tweezers
Show abstract
In order to develop the near- field optical tweezers with perfect function , We design the near-field optical fiber optical
tweezers basing on the multi-core of the optical fiber. Combining the total internal reflection and multi-core optical
fiber, we form evanescent wave on the fiber water interface forming , and realize the capture of object .It can separate the
near-field optical tweezers and its control from the microscopic observation system effectively, so It enhance the
operability of near-field optical tweezers and the ability of active capture greatly. The Multi-core optical fiber constitutes
the Near-field optical tweezers, the superposition of the coherent light from opposite transmission forms a area of capture.
Interference effect makes light intensely, at the same time the capture space becomes more and more narrow. They can
improve the capture function of the new generation of all-fiber near-field optical tweezers greatly. And we quantitatively
calculating the optical trap force of the micron-grade particle. In this passage, there is a new progress in setting up the
near field optical tweezers' model and the calculation method. Moreover, it improves the using value of the near field
optical tweezers technology in the life sciences.
Research on the h-BN films for high frequency SAW devices
Show abstract
Hexagonal Boron Nitride (h-BN) films For high-frequency SAW devices were deposited on
Ti/Al/Si(111) wafers by RF magnetron sputtering. The structure of h-BN films was investigated by
fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) spectra. And the surface
morphology and piezoelectric properties of h-BN film was characterized by atomic force microscopy
(AFM). And the characterization results show that when the RF power is 300w and other experimental
parameters were fixed, h-BN films was in high purity and the c-axis oriented, h-BN films was in high
purity and the c-axis oriented, and the particles of which are uniform and compact, roughness is
2.63nm with piezoelectric and piezoelectric response even, meet the requirements of high sound
propagation speed and excellent piezoelectric for high frequency SAW devices. The studies of
piezoelectric test of thin films have shown that PFM test method of atomic force microscopy was
suitable for characterization of piezoelectric and properties of the piezoelectric response distribution of
nano-structure semiconductor thin film.
Enhanced infrared normal spectral emissivity of microstructured silicon at 200 to 400 degrees C
Show abstract
The infrared normal spectral emissivity of microstructured silicon prepared by femtosecond laser was measured for the
middle infrared waveband at temperature range 200 to 400°C. Compared to that of flat silicon, emissivity was enhanced over the entire wavelength range. For a sample with different spike height, the max emissivity at a temperature of 300°C emissivity nearly reaches to 0.99 . Although the average emissivity is not very higher, it can be used stably at more wide temperature ranges. These results show the potential for microstructured silicon to be used as a flat blackbody source or
silicon-based devices.
Micro/Nano Manufacturing and Metrology III
Ultra-precision turning of complex spiral optical delay line
Xiaodong Zhang,
Po Li,
Fengzhou Fang,
et al.
Show abstract
Optical delay line (ODL) implements the vertical or depth scanning of optical coherence tomography, which is the most
important factor affecting the scanning resolution and speed. The spinning spiral mirror is found as an excellent optical
delay device because of the high-speed and high-repetition-rate. However, it is one difficult task to machine the mirror
due to the special shape and precision requirement. In this paper, the spiral mirror with titled parabolic generatrix is
proposed, and the ultra-precision turning method is studied for its machining using the spiral mathematic model. Another
type of ODL with the segmental shape is also introduced and machined to make rotation balance for the mass
equalization when scanning. The efficiency improvement is considered in details, including the rough cutting with the 5-
axis milling machine, the machining coordinates unification, and the selection of layer direction in turning. The onmachine
measuring method based on stylus gauge is designed to analyze the shape deviation. The air bearing is used as
the measuring staff and the laser interferometer sensor as the position sensor, whose repeatability accuracy is proved up
to 10nm and the stable feature keeps well. With this method developed, the complex mirror with nanometric finish of
10.7nm in Ra and the form error within 1um are achieved.
Simulation research on diamond cutting of mold steel using SPH method
Xiaoguang Guo,
Yanjun Wei,
Zhuji Jin,
et al.
Show abstract
The theory and application of SPH (Smoothed Particle Hydrodynamics) is presented. A Langrangian SPH model is
conducted using the LS-DYNA software. As a recently developed and promising method, particles are used in SPH as a
substitute for mesh and large material deformation is easily handled. Material separation is well achieved through
defining nodes to surface contact. The cutting process of 4340 steel is simulated with SPH method. The process of chip
formation is depicted well through the natural flow of SPH particles. The stress distribution and changes of cutting force
displays the constitutive behavior of material during cutting. And the maximum value of Von Mises stress, shear stress
and plastic strain are concentrated at primary deformation zone, especially near the tool tip.
The influence of refractive index profile on the numeric aperture in a double-layer large-core fiber
Show abstract
A special designed fiber with double layers of cores was investigated theoretically and experimentally. This fiber is
widely used in astronomy to transform light from the telescope to the optical spectrum analyzer. The refractive index
profile of this fiber was measured firstly. The testing result showed that the fiber has three layers of refractive index. A
special layer of the highest refractive index is between the uniform general fiber core and the general
low-refractive-index fiber cladding. This highest layer has higher local numeric aperture (NA), which can absorb more
light when the incidence angle is little larger. A series of experiments have been done to prove that the NA is larger than
normal fibers due to the higher-index layer. Two special incidence angles were measured respect to uniform and circle
mode pattern.
A new kind of high birefringence photonic crystal fibers with square-lattice cladding
Show abstract
We design a new kind of high birefringence photonic crystal fibers with square-lattice cladding.
Through changing the size of only four air holes in the x and y direction respectively, the birefringence is highly increased. It reaches to 1.643×10-3 when the wavelength is 1.8μm. Based on the finite element
method, the mode fields, dispersion and confinement loss of this kind of photonic crystal fibers are all analyzed.
Analysis of the vectorial diffraction characteristics of grating light modulators for MOEMS spectrometer
Show abstract
Grating light modulators are the key wavelength scanning devices for a MOEMS spectrometer. In this paper, we
build a vectorial diffraction model of grating light modulators theoretically based on Finite Beam Rigorous Coupled
Wave Analysis theory. Then we calculate the diffraction efficiency of grating light modulators at the spectral range from
900nm to 1700nm. The numerical spectra indicate that the grating light modulators can realize wavelength scanning by
changing the distance between the upper and the bottom layers. The grating light modulator can act as a programmable
pixilated optical switch with high contrast. The diffraction efficiency is stable when the θ changes from -10 degrees to
10 degrees and the Φ changes from -30 degrees to 30 degrees. The effects of the bandwidth on the diffraction
efficiency of the grating light modulators can be ignored. The average on state diffraction efficiency is 0.83 and the
average off state diffraction efficiency is 0.05 when the grating light modulators chip has 256 pixels. The experimental
results show that the vectorial diffraction model is more efficient than the scalar diffraction model.
VLS growth of GaAs/InGaAs/GaAs axial double-heterostructure nanowires
Show abstract
GaAs/InxGa1-xAs/GaAs double-heterostructure nanowires were grown by Metal-organic Chemical Vapor Deposition on GaAs (1 1 1)B substrate using the vapor-liquid-solid growth method. By tuning the In content(x) from 0.2 to 1, we fabricated several GaAs/InxGa1-xAs/GaAs nanowire heterostructrues with different InxGa1-xAs parts and studied their characteristics. We found that all the InGaAs segments were successfully grown on GaAs sections, while the InAs nanowires were grown kinked or downward. By inserting a composition-graded InxGa1-xAs buffer segment between GaAs and InAs nanowires, high yield of straight
GaAs/InxGa1-xAs/GaAs nanowire heterostructrues were realized.
Poster Session: Micro/Nano Manufacturing and Metrology
Study of the vapor cell size at high sensitive Cs magnetometer
Jiuxing Li,
Qiang Liu,
Junhai Zhang,
et al.
Show abstract
The spin-exchange relaxation free (SERF) magnetometers are the most sensitive atomic magnetometers, the optimum
sensitivity of which is on the order of 0.1 fTHz-1/2. The size of the vapor cell is important in the miniaturization of the Cs
vapor magnetometer, for it determining other components'. The more importance is dependence of the spin-destruction
rate, which is the maximum relaxation rate in the SERF regime. This paper presents the design of the vapor cell at Cs
SERF magnetometers and the discussion of the highest sensitivity achieved in different sizes.
Spatial separation on the reflected intensity of electromagnetic wavepackets in single film structure
Yuan Zhao,
Ming-Yu Sheng
Show abstract
The spatial effect of the interference of electromagnetic wave packet has been analyzed for the film structure considering
the spatial separation among the multiple reflections. The reflected intensity of polarized electromagnetic wave packet is
different considering with and without spatial separation effect. There is significant difference occurred between the
situations of the interference with or without consideration of the spatial effect. When the phase delay δ = nπ (n∈1-6).
It will be reasonable to obtain the reflected intensity by neglecting the spatial separation only for the thinner film with the
thickness much smaller than the wavelength accompanied with the condition to satisfy that δ < π, otherwise, the intensity
equation used for the periodic or non-periodic structures will be modified by including the spatial separation in the data
analysis and applications.
Characterization of the polarization beam splitters based on optical micro/nano-fiber
Show abstract
The characteristics of the polarization coupling of two optical micro/nano-fibers (MNFs), which are placed close and
parallel each other, were investigated by three dimension full vector beam propagation method (3-D FVBPM). The
analytical results of the polarization coupling show that a polarization beam splitter (PBS) device can be constructed
based on the coupling of two parallel and close MNFs. In order to optimize the polarization splitting performance of the
device, the geometric parameters of the PBS, such as the diameter of optical MNFs and the gap between them were
investigated through numerical stimulation. The optimal parameters are diameter of 0.9 μm, gap of 0.5 μm and length of
approximately 218 μm respectively. Additionally, fabrication tolerances of each parameter for the polarization splitter
PBS were also investigated. In the case of incident wavelength at 1550 nm, and the polarization extinction ratio of both
output ports of PBS larger than 15 dB, the fabrication tolerances for bandwidth and overlapping length are 10 nm and ,
±10μm , whereas approximately -3nm~2nm for tolerances in the diameter and gap.
Surface plasmon polaritions excitation by radially polarized vortex beams
Show abstract
In the past several years, surface plasmon polaritons (SPPs) excitation by vector beams or vortex beams has been greatly
studied, and many significant achievements have been obtained, which show wide applications in near-field optics. In
the paper, we study SPPs excited by radially polarized vortex beams, and concentrate on the influence of the phase
distribution of vortex beams to SPP field distribution. Based on the vector diffraction theory, the expressions for SPP
fields excited by radially polarized vortex beams are derived, and the orbital angular momentum (OAM) is calculated.
We numerically simulate the intensity and phase distributions of SPP fields excited by radially polarized vortex beams
with different topological charges, and analyze the corresponding orbital angular momentum (OAM). The results show
that by changing the topological charge, we can flexibly modulate the intensity and phase distribution, and control the
OAM, which presents us with more useful applications in special fields, such as optical trapping, near-field optical
devices, particles rotation, and so forth.
Subwavelength binary blazed grating optical switch based on TiO2-on-SiO2
Show abstract
A high-perform and compact subwavelength binary blazed grating optical switch was designed based on
TiO2-on-SiO2. By appropriate choice of grating parameters including thicknesses, periods, height, and fill factor, to
optimize the diffraction properties, a relative high diffraction efficiency and large diffraction angle was obtained
simultaneously. The diffraction efficiency of the first switching channel is about 80% with a 45° diffraction angle, and
the diffraction efficiency of the second channel is around 90% with a 30° diffraction angle. The device layout is simple,
feasible, one-step etch, and compatible with standard CMOS technology processing.
The research of measuring special optical fiber refractive index profiles by refracted near-field method
Show abstract
Refracted near-field method is a very mature and reliable method for the measure of fiber refractive index profiles. In
this paper, we use refracted near-field technique and set up the experimental device to measure special optical fiber
refractive index profiles. We build a simulation model which refers to air-core photonic crystal fiber based on refracted
near-field method, determine the structure parameters and the relationship between refractive index profiles and light
intensity distribution, calculate fiber refractive index profiles deviation caused by the special fiber structure, and give the
correction method. The experimental result is modified by the above and obtains a good treatment effect.
Calculation of duty cycle of beam sampling grating mask and analysis on diffraction efficiency uniformity of beam sampling grating
Xiaobin Xia,
Xinrong Chen,
Jianhong Wu
Show abstract
Cr mask is applied to fabricate beam sampling gratings (BSG) used in inertial confinement fusion (ICF).
There are requirements on both first-order average diffraction efficiency and uniformity diffraction
efficiency of BSG, so duty cycles of Cr mask grating must be measured to analyze the diffraction
performance. The special Cr mask is one kind of grating with curved fringes and differing periods. In this
paper, a method which can calculate duty cycles of Cr mask by measuring the zeroth-order diffraction
efficiency is introduced. Based on rigorous coupled wave analysis (RCWA) theory, this method takes
curved fringes as straight, and then calculates duty cycles under certain diffraction efficiencies by using the
drawing of the change of diffraction efficiencies against the change of duty cycles and periods. A duty
cycle can be found at a very diffraction efficiency and period. With duty cycles obtained, average
diffraction efficiency and diffraction efficiency RMS can be calculated at certain etch depth. Also an
example is given.
Fabrication of annular waveguide layer capillary optical fiber preform and temperature field distribution during fiber draw
Show abstract
In this paper, we demonstrate a novel kind of annular waveguide layer capillary optical fiber perform
which is composed of cladding, optical waveguide layer and central air hole. On the other hand, we
fabricate a capillary optical fiber with an MCVD method using an advanced graphite furnace to heat
and a specially made fiber drawing tower. The cross-section drawings of the optical fiber and the
refractive index distribution are shown. Accordingly, we give cross section of capillary optical fiber
and refractive index distribution profile. Moreover, by combining non-stable Fourier Heat-Conduction
theory with fiber drawing technology, the simplified temperature field transmission model during
capillary optical fiber preform drawing is established, and the temperature field distribution equation of
the perform neck-down region is deduced. Meanwhile, we obtain the relationship between the
temperature distribution of the neck-down region and the speed of preform feed and the furnace
temperature through the numerical simulation. The conclusion shows that the high-qualified annular
waveguide layer capillary optical fiber can be gotten when the temperature field distribution of the
capillary optical fiber perform neck-down region is near to steady state, which well agrees with the
experiment result.
The polishing detection method of side-polished fiber
Show abstract
Micro crack and pits of Side-polished fiber (SPF) is polished by fine sand paper and by an arc discharge, and their effects
are compared. When there is no light through SPF after polishing, we will find that using an arc discharge method is
better than fine sand paper polishing method especially their images being compared. When light passes SPF after
polishing, we will find that transmitted light of SPF by using an arc discharge method is less than the others. In
conclusion, using an arc discharge method is obviously better than fine sand paper polishing method.
Design of micro-optical tweezers
Show abstract
Conventional optical fiber tweezers are unsuitable for operation inside cells, due to their big-size
fiber tip to realize beam focusing. In this letter, new
micro-optical tweezers with no focusing are
demonstrated, which only demand a uniform thin-fiber to realize 3D capture and manipulation. The
fused biconical taper method is adopted to produce micro-optical tweezers with a diameter of 0.75 μm,
the finite-difference time-domain (FDTD) calculation method is used in the simulation and in the
discussion of trapping ability, and the possibility of using this method is confirmed with experiments.
These optical tweezers have a small size, tight structure, and simple production method, and it is hoped
that they will become an effective tool in cell capture and manipulation.
A method of fabricating blazed grating by homogenous grating mask
Minghui Chen,
Quan Liu,
Jianhong Wu
Show abstract
In this paper, a new approach has been proposed to fabricate holographic blazed grating. Firstly, a rectangular or
trapezoidal grating is fabricated by the combination of photoresist ashing and reactive ion beam etching, and then blazed
grating can be achieved by etching rectangular or trapezoidal grating. With this approach homogenous mask profile can
be precisely controlled. The result we get by simulating the evolution of rectangular mask for ion beam milling with
advanced segment motion algorithm which turns out to be similar with the experimental results. The blazed grating with
a line density of 1200 lp/mm is fabricated by above method, and then the blaze angle and anti-blaze angle are measured
by Scanning Electron Microscope (SEM). Obtained result shows that blazed grating has 7.1 degree blaze angle and about
22.5 degree anti-blaze angle.
Research on the property of electro-deposited Ni-Fe-SiC alloy for MEMS
Show abstract
Electrolytic codeposition technique was adopted in the deposition of Ni-Fe-SiC composite coating on stainless steel
substrate, using nickel alloyed with iron as the binder phase with SiC as dispersed particles. The results indicated that the
deposit with SiC nanoparticles was level and compact; the
crystal-planes of the deposit were (111), (220) and (200). The
resistivity of deposit was about 30μΩ•cm. when the Fe(wt.%) ranged from 10% to 50% in the deposit, the electrodeposit
Ni-20%Fe-SiC has a strong paramagnetism effect with the smallest coercivity of 2.75×10-2 A/m. The remanence showed
a monotonic decrease with the increasing iron content in deposit. Which proved that the electroformed Ni-Fe-SiC alloy
has good electromagnetic property and higher corrosion resistance (with the corrosion rate 0.17 mg/dm2 per hour) than
those of electroforming Ni-Fe alloy. It is a promising material in the fabrication of micro actuator.
Design and fabrication of the progressive addition lenses
Linling Qin,
Lin Qian,
Jingchi Yu
Show abstract
The use of progressive addition lenses (PALs) for the correction of presbyopia has increased dramatically in recent years.
These lenses are now being used as the preferred alternative to bifocal and trifocal lenses in many parts of the world.
Progressive addition lenses are a kind of opthalmic lenses with freeform surface. The surface curvature of the
Progressive addition lenses varies gradually from a minimum value in the upper area, to a maximum value in the lower
area. Thus a PAL has a surface with three zones which have very small astigmatism: far-view zone, near-view zone, and
intermediate zone. The far view zone and near view zone have relatively constant powers and connected by the
intermediate zone with power varies progressively. The design and fabrication technologies of progressive addition
lenses have fast progresses because of the massive development of the optical simulation software, multi-axis
ultraprecision machining technologies and CNC machining technologies. The design principles of progressive addition
lenses are discussed in a historic review. Several kinds of design methods are illustrated, and their advantages and
disadvantages are also represented. In the current study, it is shown that the optical characteristics of the different
progressive addition lenses designs are significantly different from one another. The different fabrication technologies of
Progressive addition lenses are also discussed in the paper. Plastic injection molding and precision-machine turning are
the common fabrication technologies for exterior PALs and Interior PALs respectively.
Research on key technique of microscopy three-dimensional image reconstruction based on piezoelectric ceramics
Jianhua Wang,
Zexin Xiao
Show abstract
Due to the limited depth of focus of microscope objective, a series of images taken from different
sections and directions are needed to reconstruct 3D microscopy image. In this paper, we present a
novel method which utilizes piezoelectric actuator, high magnification microscopy system without
mirror and single CCD to observe micro-objects and reconstruct its three-dimensional image. Inverse
piezoelectric effect of piezoelectric ceramics have some superior characteristics, such as high
positioning resolution, high positioning accuracy, etc. And piezoelectric actuator possess the
advantage of small-size, strong-power and easy- to-integrated as well. Based on these points, we
designed a 360° rotation and tilt positioning platform. In this platform, Piezoelectric actuator is
employed to ensure the positioning accuracy at axis-Z direction. At the same time, Motion of 360°
rotation and tilt can be controlled precisely using stepping motor controlling technology. Furthermore,
finite element methods (FEM) analyze software--ANSYS is used to analyze the rigidity, stress and
structure optimization of the platform. This rotation and tilt mechanical positioning platform can help
the single CCD to get clear, complete-view two dimensional images. This method paves the way for
three-dimensional reconstruction of micro objects. Experiments demonstrate that this 360° rotation and
tilt positioning stage is structure-simple and high-accurate. It can be widely used in micro-structure
observing and three-dimensional image reconstruction among mechanics, materials and biology, etc.
Study on infrared absorption of tungsten nanofilms
Show abstract
Thin metallic films have several potential applications in MEMS field, and one of them is used as infrared absorber. In
this paper, we first build a model of metallic infrared absorption and then discuss the transmission characteristics of
infrared through metal and dielectric film. For a thin film material, the maximum absorption will occur when its sheet
resistance equals to the impedance of free space. In order to verify the absorption property, tungsten (W) nanofilms with
different thicknesses have been deposited and their characteristics of infrared absorption were experimentally studied.
The infrared absorbance of W nanofilms increased as the thickness of the films increased; more than 50% IR radiation
could be absorbed by W nanofilms at the wavelength of 8-12 μm.
Low chromatic aberration of gradient refractive index rod lens for K+/Tl+ ion exchange
Show abstract
In this paper, the oxide compositions model (OC model) is established for discussing the chromatic aberrations of
gradient refractive index rod lens. The chromatic aberration for K+ /Tl+ ion exchanges is discussed based on the OC
model and the Huggins-Sun-Davis (HSD) model. Theoretical result indicates that the function value mainly depends on
base glass properties and nature of exchanging ion pairs, and hardly depends on the quantity of ion exchanging.
Experimental results show that the chromatic aberrations using the OC model have smaller errors than them using the
HSD model. The estimating average error between the OC model and the HSD model is -0.051 for the K+ /Tl+ ion
exchanges.
Research on coupling efficiency of optical coherence tomography system with gradient refractive index rod lens
Show abstract
Coupling efficiency equation of optical coherence tomography system with gradient refractive index rod lens is
established and discussed theoretically and experimentally. The experimental result is consistent with the theoretical
result. The higher coupling efficiency of optical coherence tomography system can be obtained if the θ which is the
angle between mirror and y axis should be smaller than 0.5 degree.