Chinese Version Light学术出版中心
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Issue 1 ， 2017
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Interference fringe phase locking system
Abstract：The phase drift leads to low exposure contrast in interference lithography system. In order to effectively suppress the phase drift of interference fringe, an Acousto-Optic Modulator (AOM) was employed to modulate the frequency of interference beam in real time. The characteristic of phase drift was analyzed, indicating that the main disturbance came from air turbulence with frequency within 0~5 Hz. The relationship between phase drift and exposure contrast was deduced by numerical analysis, and the target Keywords：interference lithography;phase lock;exposure contrast;Acousto-Optic Modulator(AOM);RTX- 86
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Published：2020-07-07 -
Coordinate-origin calibration of removal function in Magnetorheological Finishing
Abstract：In order to realize determined fabrication by the Magnetorheological Finishing(MRF), the coordinate origin of removal function was calibrated according to the lowest point of polishing wheel. The generation of removal function and the distribution of removing rate were analyzed. Then the coordinate relationship between the lowest point of polishing wheel and the testing probe was deduced by using a standard cylinder, realizing the precise alignment of optical elements. The removal function was tested on spe Keywords：optical fabrication;Magnetorheological Finishing(MRF);removal function;coordinate-origin calibration- 133
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Published：2020-07-07 -
Online measurement of atmospheric density based on space vehicle platform
Abstract：In view of the high-altitude atmospheric density fluctuation and the difficulty to identify aerodynamic characteristics of the aircraft in orbit, a technical solution for atmospheric density measurement by lidar based on Rayleigh scattering principle was proposed. The online data of atmospheric density at different distances was acquired through the analysis of the laser backscattering Rayleigh optical cylinder, which was captured by the Electron-Multiplying Charge Coupled Device (EMCCD) in the measuring flow field based on the principle that the density of gas molecules is in direct proportion to Rayleigh scattering intensity. Furthermore the atmospheric density online measuring instrument was developed and calibrated. Experimental and calibration results show that the online measurement precision of atmospheric density is controlled within 5%. The instrument has a promising application in optimization of spacecraft appearance and improvement of aerodynamic identification.Keywords：lidar;atmospheric density;Rayleigh scattering;spacecraft- 89
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Published：2020-07-07 -
Characteristics of optical band gap of tantalum oxide thin film deposited by ion beam sputtering
Abstract：The Ta2O5 thin film is one of the most important high refractive materials in the range from visible to near infrared. This paper researched the optical band gap of the Ta2O5 thin film which was deposited by the Ion Beam Sputtering (IBS). The optical band gap was characterized by the Cody-Lorentz dispersion model. Particularly, the correlations of the band gap and the Urbach with technological parameters were studied respectively. The results show that when the confidence probability is over 95%, the techno Keywords：Ta2O5 thin film;band gap;Urbach energy;preparative parameters;influence coefficient- 102
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Published：2020-07-07 -
Passive ranging using oxygen A-band and random Malkmus model
Abstract：Aiming at the slow calculation speed both of monochrome transmission based on Beer-Lambert Law and other transmittance models, the absorption features of oxygen A band was analyzed and algorithms of oxygen absorptivity in atmosphere was investigated in order to realize real-time and high-efficient passive ranging of infrared targets. The absorption spectrum and distribution characters for oxygen A band were analyzed. The passive ranging model based on random Malkums mode was built by introducing the random Keywords：infrared target;transmittance measurement;molecular oxygen A-band;random Malkmus band model;passive ranging;band average absorption- 85
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Published：2020-07-07 -
Phase evolution of inverse Doppler effect in two-dimensional photonic crystal
Abstract：The inverse Doppler effect in two dimensional photonic crystal with negative index was proved. In order to analysis the phase evolution of light propagated through this effect, the negative refraction was simulated in static photonic crystal by the Finite Difference Time Domain (FDTD) method. Subsequently, the Bloch wave along the propagating direction was analyzed based on the Fast Fourier Transform (FFT) method. Then, the components were retrieved by iFFT method from the filtered spectrum. The phase evolu Keywords：photonic crystal;inverse Doppler effect;negative refraction;phase evolution- 100
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- 15
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Published：2020-07-07 -
X-ray luminescence computed tomography based on improved spectral projected gradient algorithm
Abstract：X-ray Luminescence Computed Tomography (XLCT), a novel imaging technique which can obtain anatomical structure and functional information simultaneously, has an important application prospect in early tumor detection and radiotherapy. But due to the less measurement and complex imaging model, the tomography reconstruction always is a challenging problem. This paper presents a gradient algorithm based on Non-monotone Barzilai-Borwein(NBBG) to obtain the optimal solution of the objective. In each iteration, a Keywords：optical molecular imaging;X-ray Luminescence Computed Tomography(XLCT);image reconstruction;gradient algorithm- 94
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Published：2020-07-07 -
Sliding type fiber Bragg grating displacement sensor
Abstract：In order to overcome the negative influence of elasticity coefficient changeability of force-transmitting medium and directional movement of sliding block on the measurement accuracy of existing fiber Bragg grating (FBG) displacement sensors, a novel sliding type FBG displacement sensor was investigated. Special design and measures were adopted, including perpendicular sliding surface to the constrain face of sliding block, constant-strength beam with altered cross-section, and circular sliding surface of t Keywords：optical fiber sensor;fiber Bragg grating(FBG);displacement sensor;cantilever;equal-strength beam- 277
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- 29
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Published：2020-07-07 -
Transmission peak with narrow bandwidth in single optical resonator induced-transparency
Abstract：Induced-transparency based on optical resonator structure is usually generated by utilizing double optical resonators. However the induced-transparency is not stable due to the detuning between resonators. In this paper, stable induced-transparency, of which the transmission peak has high transmittance and narrow bandwidths, was achieved by using a single optical resonator. First a single optical resonator self-interference structure was established, and the transmission spectra of the structure were discus Keywords：optical resonator;induced-transparency;transmission peak with narrow bandwidth;optical measurement;filtering- 90
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Published：2020-07-07 -
Design of multilayer stacked terahertz communication lens antenna
Abstract：In order to improve the gain and directionality of terahertz communication antenna, a cross-like rings stacked lens antenna was proposed in terahertz atmospheric transmission I window. The lens antenna was consisted of a diagonal horn antenna and a multilayer stacked lens. The diagonal horn antenna was adopted as the primary feed and the multilayer comprised cross-like rings. Far field characteristics of the lens antenna was studied by using Fresnel-Kirchhoff diffraction theory and paraxial approximation. F Keywords：terahertz communication;Fresnel-Kirchhoff diffraction theory;lens antenna;diagonal horn antenna;far field characteristics- 146
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Published：2020-07-07 -
Radiometric calibration of photographic camera with a composite plane array CCD in laboratory
Abstract：To eliminate the serious vignetting phenomenon and to solve the difficulty of choosing a relatively positioning target value problems among CCDs during the radiometric calibration of the whole image plane of the photographic camera with a composite plane array CCD, a method for radiometric calibration of multi-CCDs was proposed. After the dark signal calibration on each pixel, the gray value of the pixel in the vignetting area was revised, and by choosing the appropriate relative calibration target gray val Keywords：radiometric calibration;non-uniformity;vignetting;composite plane array CCD- 113
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Published：2020-07-07
Modern Applied Optics
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Application of composite sliding mode control on motion platform of PMLSM precision laser cutting
Abstract：A composite sliding mode control method, which was based on the traditional double power sliding mode reaching law method, was adopted for the requirements of low chattering, high-performance and strong robustness on the motion platform of permanent magnet linear synchronous motor precision laser cutting. A variable boundary layer of double power reaching law with sliding mode disturbance observer has been proposed in this paper. The method of variable boundary layer is a trade-off between control precision Keywords：permanent magnet linear synchronous motor;composite sliding mode control;sliding mode disturbance observer;position servo;variable boundary layer- 115
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Published：2020-07-07 -
Ultra-precision grinding process of high-gradient thin conformal aspheric on ALON ceramic
Abstract：In order to realize the ultra-precision grinding of high-gradient thin conformal aspheric on ALON infrared ceramic, the material property of ALON and the structured feature of high-gradient thin conformal aspheric was analyzed firstly. The precision jig was design and the main dimensions were optimized by finite element method. Secondly, the ALON grinding experiments were implemented. The results indicated that although the roughness would reduce with the decrease of workpiece spindle speed and wheel abrasive size, the effect of abrasive size on roughness was more significant. Finally, the ultra-precision grinding procedures were established for ALON high-gradient thin conformal aspheric. The form accuracy PV value of ground ALON workpiece was 2 μm, while the surface roughness was 8.6 nm.Keywords：high-gradient thin structure;conformal aspheric;ALON;ultra-precision grinding;jig design- 82
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Published：2020-07-07 -
Atomic step morphology research of LED sapphire substrate polishing surface and its periodicity
Abstract：Surface quality of LED sapphire substrate influences epitaxy quality greatly, and further influences the performance of LED devices. After the chemical mechanical polishing (CMP) of slurry including Al2O3 abrasive and SiO2 abrasive of sapphire grinding wafer, finally ultra smooth surface of sub-nanometric roughness was achieved with surface roughness reaching 0.101 nm measured by atomic force microscope (AFM) and atomic step morphology was presented. Using Zygo profiler and AFM to observe the variations of Keywords：chemical mechanical polishing;sapphire;atomic step morphology- 108
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- 25
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- 7
Published：2020-07-07 -
Heat and mass transfer characteristics of submarine cold-thermal wake in the infrared detection
Abstract：The three-dimensional model of 1/72 LSII nuclear submarine was established using the finite volume method, and the simulation of high-speed rotating propeller and temperature-density stratified seawater were realized combining the frame motion, user defined functions and physical polynomial profile. Based on this model, the influences of factors such as high-speed rotating propeller, temperature-density stratified seawater and high-temperature thermal spray on the heat and mass transfer characteristics of s Keywords：thermal wake;rotating propeller;temperature-density stratification;heat and mass transfer characteristics;finite volume method;infrared detection- 125
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- 7
Published：2020-07-07 -
Trans-scale assembly method of micro-particles in 3D space
Abstract：For 3D space assembly of micro-particles, the column cavity assembly of micro-particles with diameter of more than a dozen microns and cavities with diameter of several hundred microns was determined as the research object, and a trans-scale assembly method research of micro-particles in 3D space was developed. Firstly, for the problem that micro-particles are hard to be gripped and released because of micro-force from substrate, the micro-force of micro-particles was analyzed, and a micro-gripper based on Keywords：micro-particle;micro-grip;space assembly;micro-vision;micro-assembly- 95
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- 2
Published：2020-07-07 -
Shock reliability enhancement by flexible stop for MEMS inertial switch
Abstract：To improve the shock reliability of the MEMS inertial switch, a flexible stop structure was proposed. Firstly, the stop collision model was established using the theory of continuous contact force, and the response characteristics of the switch in different stop modes were researched conducting simulation on the model through Simulink. Then, from the perspectives of space-efficient and the stress concentration, the cantilever type and plane micro-spring type stops were discussed and the stop structure was d Keywords：MEMS;inertial switch;shock reliability;flexible stop- 133
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- 19
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- 4
Published：2020-07-07 -
Meter-scale thin film coating equipment based on meniscus-coating technology
Abstract：The meniscus chemical coating technology becomes a very promising new chemical thin-film coating technology after traditional coating technologies such as spin-coating and spray coating due to its merits of large area, low-cost and high efficiency. To meet the requirements of one national major projects on the meter-scale chemical thin film coating of optical component surface, based on the systematical research of the meniscus chemical film coating principal, static and dynamic gluing experiments were resp Keywords：chemical coating;optical components;meniscus;large area;gluing- 108
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- 16
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- 0
Published：2020-07-07 -
Velocity profile measurement of oil films in a confined gap based on FRAP
Abstract：The flow of lubricant oil films in confined gaps of micro-scale is a significant factor to affect load-carrying capacity of lubrication films in precision machines and micro-electro-mechanical systems (MEMS). In order to research the lubricating property of thin lubricant film the paper established through-thickness velocity profile measurement system and carried out a on-line situ measurement on through-thickness velocity profile of thin oil film under confined micro-gaps, based on fluorescence recovery af Keywords：fluorescence recovery after photobleaching(FRAP);micro-gaps;lubricant oil film;flow velocity measurement;Couette flow- 123
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Published：2020-07-07 -
Fast acquisition of time optimal sliding model control technology for photoelectric tracking system
Abstract：Atime optimal sliding model controlwas proposed based on the fast acquisitionprocess of photoelectric tracking system. The sliding mode surface function of the control wasoptimal motion trail of time optimal control, which guaranteed that the system state variables slide along the optimal tracks; relevant exponential reaching lawwas designed to make the variables closer to sliding mode surface quickly and stably. Simulation and experiment research were carried out based on the capture targets of step signal Keywords：photoelectric tracking system;acquisition;time optimal control;sliding model control- 108
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Published：2020-07-07 -
A method for fluid velocity vector measurement using thin film Lamb wave resonator
Abstract：The trend of further research of the micro flow sensor is higher quality factor and sensitivity in the field of velocity measurement. In this letter, a new type of double-ended enhanced film resonance structure was proposed to obtain high quality factor of the Lamb wave sensor. The vector measurements of the liquid flow velocity can be achieved by using the evanescent wave, which exists around the membrane-liquid interface of one antisymmetric mode(A01) of this Lamb wave sensor. The quality factor for the p Keywords：thin film Lamb wave resonator;evanescent waves;antisymmetric mode;liquid flow velocity measurement- 119
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- 19
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- 6
Published：2020-07-07 -
Main axes AC servo control system for 2 m telescope
Abstract：A design method for telescope AC servo control system, based on high-power permanent magnet synchronous motor, was proposed to meet the requirement of low-speed tracking accuracy for 2 m telescope. Firstly, frequency characteristic curve of system structure was identified; secondly, a structure filter was designed according to frequency characteristic curve of the system so as to reduce the resonant amplitudes caused by structural mode; then, according to the requirements of the system control performance i Keywords：AC servo control system;2 m telescope;frequency response;structure filter;feed forward- 163
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- 7
Published：2020-07-07 -
High resolution time grating angular displacement sensor based on planar coils
Abstract：The measurement accuracy is easily influenced by non-uniformity of coil wiring and variation with time, which is originally because of the use of enameled coils in traditional time grating angular displacement sensor. For this, a new time grating angular displacement sensor based on PCB(Printed Circuit Board) technology was proposed. By arranging particular shapes of excitation and induction coils in different layers of PCB baseboard, the sensor formed two identical sensor units and they were of quadrature Keywords：angular displacement measurement;planar coil;high resolution;time grating;sensor- 138
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- 15
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- 5
Published：2020-07-07
Micro/Nano Technology and Fine Mechanics
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Research on fall detection system based on support vector machine
Abstract：Real-time fall detection has great advantages of reducing physical and psychological damage in senior citizens group after falls and improving solitude ability and health level of senior citizens. A support vector machine (SVM) algorithm, which is based on RBF (Radial Basis Function) and applied to achieve fall detection, has been proposed in order to improve accuracy rate and lower false positive and false negative rate of fall detection system on the basis of inertial sensor. First, the system completes d Keywords：fall detection;inertial sensor;machine learning;SVM;particle swarm optimization;RBF- 80
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Published：2020-07-07 -
Self-adaptative variable-metric feature point extraction method
Abstract：A feature point extraction method for self-adaptative variable-metric constructing image pyramid is proposed to accelerate the feature matching. In this method, number of FAST feature points is adopted as information content quantization in scale space representation and pyramid hierarchy is carried out according to the information difference of blurred images in the neighboring layers. By adjusting scale parameters, Uniform change of detail feature in neighboring images is realized, number threshold of mat Keywords：scale space;feature detection;feature matching;Gaussian Image- 91
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Published：2020-07-07 -
A destriping method with multi-scale variational model for remote sensing images
Abstract：Non-uniformity often occurs in multi-detectors remote-sensing imaging system, resulting in the existence of strip noise in remote sensing images. A destriping method with multi-scale variational model has been proposed on the basis of the analysis on the main sources and model of stripe noise. First, the characteristics of strip noise have been analyzed and the degradation model of the image has been formulated. Secondly, the unidirectional characteristic of strip noise and multi-scale hierarchical image de Keywords：optical remote sensing;stripe noise;multiscale hierarchical image decomposition;non-uniformity correction- 93
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- 9
Published：2020-07-07 -
Star identification algorithm based on the maximum interior angle in triangle
Abstract：As the traditional triangle star identification algorithm is insufficient, this paper proposed a fast all-sky autonomous triangle algorithm with star magnitude-independent. By structuring the maximum interior angle and two sides as a matching feature triangle, the algorithm established celestial navigation feature library which was constructed to be a hash function according to the maximum interior angle and stored into sub-blocks. ‘Edge-angle-edge’ matching mode was adopted in the process of star identific Keywords：star sensor;star identification;triangle algorithm;feature triangle- 89
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Published：2020-07-07 -
Smear correction of asynchronous binning high frame rate CCD camera
Abstract：A high frame rate imaging technology based on asynchronous timing drive and Binning technology has been applied on frame transfer CCD camera successfully. The reason why smear noise occurs in image acquisition process has been analyzed theoretically and a complete set of numerical analytic algorithm for smear correction has been carried out to restraint the smear generated in the imaging of this CCD camera, according to its continuous imaging principle. The algorithm has fully taken the effects of consecuti Keywords：asynchronous Binning;high frame rate camera;frame transfer CCD;smear correction- 139
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Published：2020-07-07 -
Feature description of exact height function used in fast shape retrieval
Abstract：In order to improve the discrimination ability and robustness of contour noise and deformation of Height Functions (HF) descriptor in the process of shape retrieval, a feature description algorithm of exact height functions is proposed in shape retrieval. Firstly, contour outside the target shape is extracted, and then exact height functions type descriptors of sampling points are constructed for dimensionality reduction. And then, the optimized parallel dynamic programming algorithm is employed in matching Keywords：shape retrieval;exact Height Functions (HF);shape precision;parallel dynamic programming- 83
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- 15
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Published：2020-07-07 -
Regularized total least squares used in remote sensing image positioning of optical line array
Abstract：In geometric positioning of optical line array remote sensing image, as it exists error on system error correction parameters corresponding coefficient matrix, a geo-positioning method of remote sensing image of optical line array based on regularized total least squares was proposed in this paper. Firstly, the collinear equation was constructed based on the definition of rational function model, Secondly, the geo-positioning and systematic error correction methods were derived by linearization. Then, the c Keywords：linear array CCD images;geo-positioning;regularized total least squares;regularization;generalized cross validation- 127
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Published：2020-07-07 -
Point cloud adaptive simplification of feature extraction
Abstract：Point cloud data, as a kind of three-dimensional information reflecting the object shape, have quite a large amount of original data, so if directly operating on excessive data, it will affect subsequent work such as point clouds reconstruction, etc. This paper proposes a novel adaptive simplification algorithm for point cloud feature extraction. First, space should be divided with respect to the original point cloud, and then k neighborhood of the point should be built, and feature parameters should be set Keywords：point cloud simplification;adaptive simplification;k neighborhood;surface fitting- 233
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Published：2020-07-07 -
Target fast matching recognition of on-board system based on Jilin-1 satellite image
Abstract：Aiming at problems such as long cycle and insufficient real time information in traditional remote sensing ground target image recognition system, an on-board target fast matching recognition platform is designed for fast on-orbit satellite recognition, and an improved feature matching recognition algorithm based on fast retinal key points (FREAK) is proposed to solve the problems of complex backgrounds and large amount of data in remote sensing image, First, we introduce the principle of on-board target re Keywords：Jilin No.1 Satellite;target recognition;FREAK feature;binary quantization- 98
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- 9
Published：2020-07-07 -
Feature Extraction of Hyperspectral Images of Weighted Spatial and Spectral Locality Preserving Projection (WSSLPP)
Abstract：In order to improve the classification accuracy of Hyperspectral images (HSI) and preprocess HSI by effectively using the spatial and spectral information of HIS, a new spatial-spectral feature extraction method, Weighted Spatial and Spectral Locality Preserving Projection (WSSLPP) is proposed in this paper. The HSI was reconstructed combining the physical characters of HSI to avoid the interference of singular point; then the target functions of locality pixel neighbor preserving embedding (LPNPE) and loca Keywords：spatial information;spectral information;Weighted Spatial and Spectral Locality Preserving Projection (WSSLPP);Hyperspectral images (HSI);feature extraction- 87
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Published：2020-07-07 -
Methods of monocular pose measurement based on planar objects
Abstract：A plane objects pose measurment algorithm based on monocular vision is proposed aiming at close-range pose measurement requirements in space rendezvous and docking. In order to facilitate the adjustment of the aerial mobile platform so as to satisfy the specific position relations, a new angle definition method is introduced, the three angles defined by which can be used as the feedback of the platform attitude adjustment and they are not restricted by the order of rotation. The three angles and position ve Keywords：monocular vision;plane objects;pose measurement;space rendezvous and docking- 124
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Published：2020-07-07
Information Sciences
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