Journals >Optics and Precision Engineering
Contents
2009
Volume: 17 Issue 2
34 Article(s)
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Research Article
Research on some new mechanisms of slow light and its applications
ZHAO Yong, ZHAO Hua-wei, ZHANG Xin-yuan, YUAN Bo, and ZHANG Shuo
The last decade is of great significance for the development of slow light technology. In order to study on the slow light technology deeply, several kinds of slowing light technologies, such as Electromagnetically Induced Transparency(EIT), Coherent Population Oscillation(CPO), Stimulated Brillouin Scattering(SBS) andThe last decade is of great significance for the development of slow light technology. In order to study on the slow light technology deeply, several kinds of slowing light technologies, such as Electromagnetically Induced Transparency(EIT), Coherent Population Oscillation(CPO), Stimulated Brillouin Scattering(SBS) and photonic crystal waveguide, were contrasted and analyzed. Also some important theoretical and technical developments to improve performance of slow light in last decade were introduced, and then problems and shortcomings existing in slowing technology were discussed. Finally,this paper focuses on some novel technologies of slowing down light velocity and their primary applications. Moreover, it forecasts the future developing trends of slow light and its potential applications. Through research on slow light, results show that slow light will realize more and more significant application values in the field of optical fiber sensing and other fields..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 237 (2009)
Simulation of non-line-of-sight light propagation for multiple-scattering instance
HE Xin, JIA Hong-hui, CHANG Sheng-li, YIN Hong-wei, and YANG Jun-cai
The multiple-scattering theory based on Monte Carlo (MC) method is described in detail to calculate two typical multiple-scattering instances. With atmospheric absorption coefficient in 1.2 km-1,scattering coefficient in 1.5 km-1 and for a 1 W source, the signal energy is close to 0.27 nW at the distances of 50 m away The multiple-scattering theory based on Monte Carlo (MC) method is described in detail to calculate two typical multiple-scattering instances. With atmospheric absorption coefficient in 1.2 km-1,scattering coefficient in 1.5 km-1 and for a 1 W source, the signal energy is close to 0.27 nW at the distances of 50 m away and it decreases in exponential decay with increasing distance, when the detector and emission are in opposite directions; the signal energy is 0.23 nW at distances of 200 m away and it increases greatly with increasing distance,when the visual angle of the detector is limited by obstacles. Accordingly, a solution is presented to simulate the light propagation when the detector and emission do not have mutual scattering-substance. Experimental results show proposed simulation is correct and it is very practicable in complicated conditions..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 246 (2009)
Iterative stitching algorithm for annular subaperture testing and its experimental verification
DAI Yi-fan, ZENG Sheng-yue, and CHEN Shan-yong
In order to satisfy high precision and fast optical surface measuring, an iterative algorithm for annular subaperture stitching is discussed based on the Subaperture Stitching and Localization (SASL) algorithm. The basic theory of annular subaperture stitching is introduced, which can be divided into two parts, one is In order to satisfy high precision and fast optical surface measuring, an iterative algorithm for annular subaperture stitching is discussed based on the Subaperture Stitching and Localization (SASL) algorithm. The basic theory of annular subaperture stitching is introduced, which can be divided into two parts, one is how to determine the overlapping points precisely and the other is how to find optimal configuration. Then, how to determine the overlapping points in annular subaperture stitching is studied and the detailed procedure of the iterative stitching algorithm is presented. Finally, a paraboloid of 160 mm aperture is tested with Annular Subaperture Test(AST), tested results in PV value of 0.186λ and RMS value of 0.019λ are consistent with the auto-collimated full aperture testing. All these discussions clearly prove that the iterative annular subaperture stitching algorithm can meet the requirement for high precision testing of aspherical surfaces..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 251 (2009)
Design and stability analysis of driving system in spinning prism Q-switch
WANG Xi-jun, GENG Xiao-tao, DAI Qin, LI De-sheng... and WANG Ya-jun|Show fewer author(s)
In order to obtain a kind of spinning prism with high spinning speed, continuous adjustability and robust stability, the driving system of a high-speed motor for spinning prism Q-switch was designed. Using an AVR chip and a grid electrode driving integrating module, the high-speed motor controlled by three-phase frequeIn order to obtain a kind of spinning prism with high spinning speed, continuous adjustability and robust stability, the driving system of a high-speed motor for spinning prism Q-switch was designed. Using an AVR chip and a grid electrode driving integrating module, the high-speed motor controlled by three-phase frequency conversion was designed. The results show that the driving system of the motor can work stably when the rotation speed is less than 60.8 kr/min, which can realize “fast” shutoff of the Q-switch. The designed Q-switch is applied in Diode Pumped Solid State Laser(DPSSL), and the 14 kHz turning-off-ability Q-switch in the high repetition rate and high-power DPSSL is realized in a experiment with the rotation speed of 43 kr/min, which is the best result in the spinning mirror Q-switch by now..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 257 (2009)
Light distribution test system based on moving in plane
LING Ming, JIN Guang-yong, LIU Yi-sheng, PANG Bo1, and LIANG Zhu
To improve the accuracy of light distribution test of automotive lamp and to reduce cost, a novel light distribution test system based on moving in the plane for automotive lamp was researched to test luminance of every point on light screen. By comparing to the current rotating desk system with the best precision in CTo improve the accuracy of light distribution test of automotive lamp and to reduce cost, a novel light distribution test system based on moving in the plane for automotive lamp was researched to test luminance of every point on light screen. By comparing to the current rotating desk system with the best precision in China, the error transfer function was founded and errors of two systems were analyzed. Then, the accuracies to two kinds of test systems were tested with national benchmark lumeter. Finally, the best distance of automotive signal light was calculated from residual error norm. After testing JT200 headlamp and AD100 signal light, the experimental results indicate that the position precision of the system is 0.14 mm, which is 31 times that of the current rotating desk system, and luminance accuracy is 0.02 lx,three times that of current one. The experiment to automotive signal light shows that the best test distance for the rotating desk system is 2 m instead of 3.16 m used currently in China, and the luminance accuracy of new-style system is direct proportion to the test distance. These results can satisfy the system requirements of national standard in higher precision, rapid speed and the adjustable test distance to lamp..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 262 (2009)
Research on electrostatic deformation of membrane mirror
ZHANG Ying, and JIN Guang
To control membrane mirror figure, the physical model of Stretched Membrane with Electrostatic Curvature (SMEC) was established. The control principle of electrostatic shaping was introduced according to the balance between electrostatic force and resulting force formed by membrane deformation and the complex shaping pTo control membrane mirror figure, the physical model of Stretched Membrane with Electrostatic Curvature (SMEC) was established. The control principle of electrostatic shaping was introduced according to the balance between electrostatic force and resulting force formed by membrane deformation and the complex shaping process of SMEC. Then, taking the trisection circularity electrode for an example, the distribution characteristic of electric potential in the electrostatic field was analyzed, namely, the expression of potential function in the electrostatic field was deduced by Laplacian equation. And then, by combining the difference equation with electric potential expression, the numerical solutions of electrostatic force in single electrode mode and trisection circularity electrode mode were disposed. Finally, the calculated figure was compared with the ideal paraboloid and comparison shows that more accuracy would be achieved by multi-electrode control. The simulation and experimental results indicate that the force distribution in multi-electrode mode is more even than that in singe electrode mode, and membrane mirror of 180 mm in diameter can acquire the maximum 0.001 094 8 mm deformation controlled by a same size single electrode under voltage of 10 000 V. The system can work steadily and safely for a long time, while the symmetry of membrane mirror is preferably..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 267 (2009)
Unfolded study on spectra by elliptical crystal spectrometer
WANG Rui-rong, and CHEN Wei-min
By coupling Elliptical Bent Crystal Spectrometer (EBCS) with X-ray CCD, a set of system (EBCS-XCCD) for measuring X-ray spectra was briefly described. The calibration procedures for absolute line and line intensity measurement were studied and formulae of identification signals were deduced according to the geometricalBy coupling Elliptical Bent Crystal Spectrometer (EBCS) with X-ray CCD, a set of system (EBCS-XCCD) for measuring X-ray spectra was briefly described. The calibration procedures for absolute line and line intensity measurement were studied and formulae of identification signals were deduced according to the geometrical parameters of EBCS-XCCD and physical optics. An example of calibrating spectra was presented with elliptical crystal of a-quartz (1 010,2d=0.852 nm ) for the 0.399~0.736 nm photon wavelength region. The spectrum intensity from laser plasma X-ray source was also obtained by the formula based on known the integrated reflectivity of the crystal, the transmission of foil and the responsivity of X-ray CCD photodiode to photons,results show that the good spectral resolution of laser-produced Al plasma is better than 1 000. The unfolded spectra by the method were compared with that of the reference [1], the results are basically identical. These data reported here indicate that this system is particularly suitable for the high-precision measurements of the spectral line profiles and positions in nonhomogeneous plasmas,and experimental results are superior to those obtained in earlier measurements, which demonstrates the EBCS-XCCD performance..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 274 (2009)
Infrared stealth technology based on performance parameters of camouflage coating
CHEN Xuan, ZHANG Jian, WANG Yan-wu, and YANG Li
On the basis of the method of numerical heat transfer,the surface temperature of target was simulated. Then, the influence of the performance parameters of camouflage coating(shortwave absorptivity αs、longwave absorptivity αl、emissivity εt) on the surface temperature of target was analyzed. Finally, the influence of thOn the basis of the method of numerical heat transfer,the surface temperature of target was simulated. Then, the influence of the performance parameters of camouflage coating(shortwave absorptivity αs、longwave absorptivity αl、emissivity εt) on the surface temperature of target was analyzed. Finally, the influence of these performance parameters on the lock-on range of infrared detection system was also analyzed. The analytical results show that all of performance parameters would affect the temperature of target. αs and αl are in direct proportion to the temperature of target, and εt is in inverse proportion to that, the influencing range could reach to 10 ℃.Moreover,the lock-on range of detection system correlates to background temperature, weather condition, capability of detector and so on, and adjusting the performance parameters to the practical condition can shorten the lock-on range to least. These results can satisfy the practical requirements of design, selection and application of infrared camouflage coating..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 280 (2009)
Effect of incident laser beam angle varying on cube corner retro-reflector measurement accuracty
LIU Wan-li, OUYANG Jian-fei, and QU Xing-hua
In order to describe the relationship between the incident angle of Cube Corner Retro-reflector (CCR) and the measurement accuracy of CCR used in laser tracker system, the working principle and reflective characteristic of CCR were analyzed. A novel approach was proposed to determine the effective reflection area of CCIn order to describe the relationship between the incident angle of Cube Corner Retro-reflector (CCR) and the measurement accuracy of CCR used in laser tracker system, the working principle and reflective characteristic of CCR were analyzed. A novel approach was proposed to determine the effective reflection area of CCR with an arbitrary incident angle and then the formula of ray cross section of CCR with varying incident angle was derived according to the effective reflection area. Accordingly, the relationship between CCR measuring accuracy and incident angle was established. The experimental results demonstrate that the CCR measuring accuracy reduces as the increase of incident angle, the CCR measuring error is the largest when the maximal incident angle is reached. The measuring error of CCR at maximal incident angle of ±35.26° is 0.050 mm, but the measuring accuracies of CCR are better than 0.010 mm when the incident angle are within ±20°, and the measuring accuracy and the stability are best only when the incident angles are within ±15°. The results show that CCR can maintain the manufacture specifications of laser tracking system only when the incident angles are within ±20°, which provides a very useful guidance for design and application for CCR..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 286 (2009)
Research of actuator arrangements for shaping aspheric surfaces
ZENG Chun-mei, and YU Jing-chi
In order to shape aspheric surfaces for ultra-thin spherical mirrors, a new method for the initial solutions of actuator arrangements solved by asphericity gradient was presented.The theoretical analysis, arrangement method and two formulas for calculating the asphericity gradient were given. As shaping an off-axis larIn order to shape aspheric surfaces for ultra-thin spherical mirrors, a new method for the initial solutions of actuator arrangements solved by asphericity gradient was presented.The theoretical analysis, arrangement method and two formulas for calculating the asphericity gradient were given. As shaping an off-axis large-aperture aspheric mirror for example, the initial solutions of actuator arrangements were obtained by two formulas above, respectively. By using Finish Element Method(FEM), the deformation analysis of shaping aspheric surfaces with form error of 21.09 nm was accomplished, and the final solutions were given. Moreorer, the optimizations of actuator arrangements were discussed. Finally, three kinds of methods for actuator arrangements were compared with each other. The results indicate that the initial solution based on average value of asphericity gradient is most similar to the final solution, which is in accord with the relation between the change rate of asphericity gradient and the surface density of actuator arrangements. The optimization can reduce the number of actuators and can improve the form error further. Under the same form error, the number of actuators by the aspheric gradient method is 1/2 or less than that by the square and circular methods; under the same actuator numbers, the RMS of form error by the aspheric gradient method is about 1/3 or less than that by the square and circular methods. These data reported here show that the aspheric gradient method is suitable to solve an initial solution of actuator arrangements in the field of shaping aspheric surfaces..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 292 (2009)
Structural optimization of double wavelength optical fiber F-P sensing system based on differential evolution algorithm
SHAN Ning, SHI Yi-kai, and LIU Xia
On the basis of Differential Evolution(DE) algorithm with strong capabilities of global searching, fast convergence speed, good robustness and easy to optimize complex problem,a technology of double wavelength stabilization is put forward to resolve the problems that optical fiber F-P sensor deviates from working pointOn the basis of Differential Evolution(DE) algorithm with strong capabilities of global searching, fast convergence speed, good robustness and easy to optimize complex problem,a technology of double wavelength stabilization is put forward to resolve the problems that optical fiber F-P sensor deviates from working point easily and causes the attenuation of output signal and the decrease of Ratio of Signal to Noise(RSN). The mathematic optimal model of double wavelength stabilization system is established, and structure of the system is optimized by using DE algorithm. The results indicate that the global optimal solution can be obtained in a shorter running time, the object is decreased by 89.46% and calculation error is less than 10-3. The results reported above prove that this algorithm is proper and feasible, and can be used for the structural optimization design of optical fiber F-P sensor..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 301 (2009)
Error propagation analysis of structured light system
XU Li, and ZHANG Zhi-jiang
To study the calibration accuracy of stuctured light system based on cross-ratio invariant,measuring error and light-plane calibration error of system are analyzed,and an error propagation model is established by employing theories of error and matrix disturbance. According to the error propagation model,the precision To study the calibration accuracy of stuctured light system based on cross-ratio invariant,measuring error and light-plane calibration error of system are analyzed,and an error propagation model is established by employing theories of error and matrix disturbance. According to the error propagation model,the precision demands of calibration parameters and samples under a special condition in measuring distance of 1 000 mm and measuring accuracy of ±0.5 mm is presented. The error propagation model is validated through experiments,experimental results show that proposed model can provide theory basis for improving measuring accuracy of structured light system..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 306 (2009)
Analysis of influence of vibration on transfer function in optics imaging system
GENG Wen-bao, ZHAI Lin-pei, and DING Ya-lin
In order to make the Opt-Mec design meet the requirements of imagine systems, the impact of mechanical vibration on the Modulation Transfer Funtion(MTF) is analyzed. By considering the form of optical imaging system to vibration and taking the MTF as an evaluation function, this paper quantitatively analyzes the impactIn order to make the Opt-Mec design meet the requirements of imagine systems, the impact of mechanical vibration on the Modulation Transfer Funtion(MTF) is analyzed. By considering the form of optical imaging system to vibration and taking the MTF as an evaluation function, this paper quantitatively analyzes the impacts of various forms of mechanical vibration on image resolution and discusses the influence of each kind of parameter on the MTF based on the knife-edge theory (Line Spread Function,LSF). These analysises provide theory basis for the intensity, rigidity and the precision design of optics machinery. Combining engineering practice, several kinds of schemes are proposed to reduce the impact of vibration on the imaging quality. Through the MTF analysis for a imaging equipment, the dynamic resolution of 22 lp/mm for a imaging equipmen is obtained,which is close to the actual photograph result. The results indicate that the analysis is correct and usable..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 314 (2009)
Processing methods of precision and ultra-precision cylindrical involute gear
WANG Li-ding, LING Si-ying, MA Yong, WANG Xiao-dong, and LOU Zhi-feng
In order to enhance technological level of gear manufacturing comprehensively, the processing methods of precision and ultra-precision cylindrical involute gears were researched. The work principles of several gear-grindings and machining statuses of ultra-precision cylindrical involute gears were analyzed and comparedIn order to enhance technological level of gear manufacturing comprehensively, the processing methods of precision and ultra-precision cylindrical involute gears were researched. The work principles of several gear-grindings and machining statuses of ultra-precision cylindrical involute gears were analyzed and compared. Then, machining of ultra-precision gear above quality 2(ISO1328:1997) was probed. Finally, the gear grinder Y7125 with big plan wheel provided with the advantages of streamline structure, high rigidity of transmission chain, high accuracy of gear-grinding and much room to modify was pointed. Research results show that the grinder Y7125 is probably to be a master grinder of ultra-precision cylindrical involute gear to produce ultra-precision gear from quality 2 to quality 1. The development of ultra-precision with quality 1 can enhance the gear normal and technological level of gear manufacturing..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 321 (2009)
Servo system of large telescope based on internal model PID control method
LI Hong-wen
On the basis of internal model PID control method,this paper researches further the servo system of a large telescope for reducing its adjusting parameters in servo control loop. The design ideals of internal model control are introduced and the algorithm of internal model control is discussed. Analysis and simulation On the basis of internal model PID control method,this paper researches further the servo system of a large telescope for reducing its adjusting parameters in servo control loop. The design ideals of internal model control are introduced and the algorithm of internal model control is discussed. Analysis and simulation results verify that the algorithm simplifies the debug process; and it is feasibility and robustability for high precision application fields. The practicability of this algorithm is verified in an actual project. The application shows that this system runs stably and accurately, and has a few adjusting parameters in servo control system.Also, there is no overshoot while the speed is high and the lowest speed can reach 15″ in stable operation. The technology and methods adopted in the system are practical and worthy to be used..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 327 (2009)
Integrating positioning X-Y stage based on bulk micromachining
WANG Jia-chou, RONG Wei-bin, LI Xin-xin, SUN Li-ning, and MA Li
In order to realize the miniaturized nano-positioning stage, a novel 2-DOF Single Crystal Silicon (SCS) nano-positioning micro X-Y stage with the function of displacement detection is successfully developed by using silicon bulk-micromachining; the X-Y stage is drived by an electrostatics comb actuator. The theories ofIn order to realize the miniaturized nano-positioning stage, a novel 2-DOF Single Crystal Silicon (SCS) nano-positioning micro X-Y stage with the function of displacement detection is successfully developed by using silicon bulk-micromachining; the X-Y stage is drived by an electrostatics comb actuator. The theories of electromechanical coupling and energy conservation are used to analyze electrostatic actuated mechanism, X-Y stage static characteristic and X-Y stage dynamic characteristic. Some failure modes of X-Y stage are also presented and the electromechanical side instability and the stable travel range of comb-drive actuators are investigated. The stable travel range depends on the finger gap spacing, the initial finger overlap and the spring stiffness ratio of the compliant suspension. Additionally, by taking into account the effect of the air damping on the X-Y stage dynamic characteristic, the maximum velocity, stable travel range and critical driving voltage are given to an experiment on closed-loop control. The experimental results indicate that the analyzed characteristics are useful in the design and control of the micro X-Y stage. Under 30 V driving voltage, the single-axis displacement output is 10 μm, and the closed-loop step response is only 2.5 ms..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 333 (2009)
Controlling design of airborne DIRCM laser pointing system
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In order to improve the control precision of the three-axis operating system used in airborne laser pointer, a simulating model is established for system analysis. A three-axis, coupling and nonlinear dynamic model is built based on Lagrange theorem, and by analyzing the velocity coupling and the dynamics coupling relaIn order to improve the control precision of the three-axis operating system used in airborne laser pointer, a simulating model is established for system analysis. A three-axis, coupling and nonlinear dynamic model is built based on Lagrange theorem, and by analyzing the velocity coupling and the dynamics coupling relationships among the axis of frames, their analytical relationships in theory are deduced. Then, according to electrics and mechanic equations of the actuator-torque motor, the open-loop transfer function matrix of the control variable is established, and a cascade compensator is designed to decouple the control system. Analysis results show that the system can satisfy the quick-response requirement at working in stablization after decoupling and adding correction function in series. The step response time are 0.45 s for the orientation frame, 0.50 s for the pitching frame, and 0.85 s for the across frame. Finally, the electro-mechanical model is verified through computer simulation, which sets a foundation and provides theoretical references for further research and design of the control system of high-precision airborne laser pointer..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 341 (2009)
Operating characteristic of rotary piezo impact drive mechanism
JIANG Nan, and LIU Jun-biao
A rotary piezo motor with adjustable preload function is designed to study the rotational motion of an Impact Drive Mechanism (IDM). The motion principles of this Rotary Impact Drive Mechanism (RIDM) are investigated, the influencing factors of driving signal, structural parameters as well as piezoelectric element on mA rotary piezo motor with adjustable preload function is designed to study the rotational motion of an Impact Drive Mechanism (IDM). The motion principles of this Rotary Impact Drive Mechanism (RIDM) are investigated, the influencing factors of driving signal, structural parameters as well as piezoelectric element on motion characteristics of the mechanism are analyzed. The research results reveal that the rotational velocity of this motor is in proportion to the frequency or the voltage of driving signal, and in inverse proportion to M/m (the ratio of the main body and the weight). The velocity decreases as the charge time increasing of piezo element. Furthermore, the results also show that the torque-speed property and forward-backward rotation of rotary motor are both different from that of traditional motor. The torque-speed curve of the rotary motor is a fold line,and the forward rotational velocity is larger than the backward rotation velocity all the time. When the frequency,voltage and the charge time are 1100 Hz,50 V and 70 μs,respectively, and M/m is equal to 8.9, rotational velocity is about 1.75°/s and the maximum torque is 0.13 N·m.These results reported here show that the rotary impact drive mechanism is a multivariable system, whose performance is decided by many factors..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 350 (2009)
Complex edge recognition algorithm of micro-accessory
ZHANG Zhi-jing, DU Fang, JIN Xin, and ZHANG Lin
In order to realize the edge recognition for micro-accessory, a new complex edge recognition algorithm for micro-accessory is proposed based on the process characteristics of micro-accessory. By extracting the edge transitional region of different micro-accessories,and the polynomial regression mathematical models of tIn order to realize the edge recognition for micro-accessory, a new complex edge recognition algorithm for micro-accessory is proposed based on the process characteristics of micro-accessory. By extracting the edge transitional region of different micro-accessories,and the polynomial regression mathematical models of transitional region are established.Then, the accurate position is obtained by process characteristics from the mathematics model. The experimental results indicate that the measurement error of 1 mm standard gauge block is 0.395 μm. After analysing the model for micro-fabrication,it comes to a conclusion that the process characteristics have greater influences on the edge of micro-accessory, so the edge recognition of micro-accessory should consider the influences of process characteristics. Proposed algorithm has considered the effects by processing characteristics and has induced a statistical scheme,so that the edge recognition result can reach to the sub-pixel level by establishing the mathematics model of transitional region. The algorithm also can offer a wide single-pixel and continuous edge,which can meet the precision measurement requirements..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 356 (2009)
Design of xPC semi-physical simulation system for small-satellite attitude control
XU Kai, CHEN Chang-qing, GUAN Wen-cui, and JIN Guang
To take advantage of the reaction flywheel to build an attitude control system for a small satellite,a semi-physical simulation plate system was designed based on the xPC real-time environment, single-axis air-bearing platform, attitude control computer, optical fiber gyro and reaction flywheel. With the system, a semiTo take advantage of the reaction flywheel to build an attitude control system for a small satellite,a semi-physical simulation plate system was designed based on the xPC real-time environment, single-axis air-bearing platform, attitude control computer, optical fiber gyro and reaction flywheel. With the system, a semi-physical simulation was verified for the small satellite control maneuver mode concerned to the reaction flywheel. The results of the simulation indicate that small-satellite attitude is maneuvered 31.57° within 50 s in better pointing accuracy and stability. The conclusion shows that according to the characteristics of the gyroscope and the reaction flywheel, the designed algorithm can meet the requirement of the maneuver on the small-satellite attitude control..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 362 (2009)
Application of graphite fiber reinforced aluminum matrix composite to body tube structure in space remote sensor
SUN De-wei, ZHANG Guang-yu, ZHANG Qi-xin, and WU Gao-hui
In order to design and manufacture more excellent space remote sensor, a new type of astronautic material — graphite fiber reinforced aluminium matrix composite (Gr/Al composite) is investigated. Several crucial technologies, such as interface reaction controls of graphite fiber and aluminum alloy, designs of fiber lamIn order to design and manufacture more excellent space remote sensor, a new type of astronautic material — graphite fiber reinforced aluminium matrix composite (Gr/Al composite) is investigated. Several crucial technologies, such as interface reaction controls of graphite fiber and aluminum alloy, designs of fiber laminating and winding are systematically studied. Then, Gr/Al composite is successfully prepared in density of 2.12×103 kg/m3; modulus of elasticity of 129 GPa and thermal expansion coefficient of 5.0×10-6 K-1. Aiming at this composite, a set of manufacture and post-processing technology is explored in detail. Moreover,the composite is applied to design of the body tube of a space infrared remote sensor for the first time. The weight of Gr/Al composite body tube is lighter 31.8% than that of titanium alloy. Finally, the body tube preparation and assemble, lens setting and calibration, random vibration test are conducted respectively. The experimental results indicate that the first order resonance frequency of body tube component is 284 Hz(more than 100 Hz,design requirement). There is not any change for optical and mechanical system after vibration test. Accordingly, above research suggests that Gr/Al composite has important use value in space remote sensing field..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 368 (2009)
Rotary stepping ultrasonic motor driven by single-phase signal
SHI Yun-lai, JIN Jia-mei, and ZHAO Chun-sheng
A rotary stepping ultrasonic motor driven by single-phase signal is proposed in this paper. It can realize driving and positioning under the same operating pattern to avoid miss steps and can solve the difficulty in designing a frictional interface between the stator and the rotor which is usually presented in the selfA rotary stepping ultrasonic motor driven by single-phase signal is proposed in this paper. It can realize driving and positioning under the same operating pattern to avoid miss steps and can solve the difficulty in designing a frictional interface between the stator and the rotor which is usually presented in the self-correction ultrasonic motors. Proposed rotary stepping ultrasonic motor is characterized by its no cumulative errors in open-loop control. Moreover,the construction of stator is designed with ANSYS software. Desiged prototype shows it runs steady without miss-step on trial, and the stall torque, stepping angle, and the error of one step are 0.003 2 N·m,7.5° and 0.6°, respectively..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 375 (2009)
Novel tailoring method for conducting and radiating electromagnetic compatibility testing of unmanned aerial vehicle
HUANG Da-qing, and Li Bo
A novel tailoring method for conducting Electromagnetic Compatibility(EMC) testing on applicable test range,frequency band and limit size is presented for better use of national military standards GJB151A and GJB152A-97. After calculations of common-mode and differential-mode on rectifier and brute force filter,the limA novel tailoring method for conducting Electromagnetic Compatibility(EMC) testing on applicable test range,frequency band and limit size is presented for better use of national military standards GJB151A and GJB152A-97. After calculations of common-mode and differential-mode on rectifier and brute force filter,the limits of CE101 testing can be broadened up to 5 dB at 400 Hz in the conditions of the power of Equipment Under Test(EUT) below 0.2 kVA and load circuit above 1 A. Based on the topology structure of switch power source and typical switch current wave, the limits in CE012 test can increase by 10 dBμV when the testing frequency band width is below 2 MHz. According to the scheme of RE101 testing, the limits of magnetic emission measured from 7 cm away emission source are 100 mG at 30 Hz, 25 mG at 60 Hz and 6.6 mG at 120 Hz. Based on the coupling mode of emission source and receive antenna, it is confirmed that the limits of RE102 should be strictly controlled in 2~30 MHz bandwidth. The UAV is tested in real flying ground by 410A susceptivity testing system and by simulated Electromagnetic Pulse(EMP) test according to military testing method GJB3567-99, the results reveal that the air-borne equipment based on this tailored testing method can work normally and do not be degraded, which shows that this tailoring method can satisfy the requirement of EMC of UAV..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 380 (2009)
Analysis on coordinate conversion error of airborne measuring device
WANG Jing, GAO Li-min, and YAO Jun-feng
In order to improve the positioning accuracy and guiding accuracy of an airborne measuring device, a mathematical model of error analysis is established based on the coordinate conversion equation from geodetic coordinates to telescope coordinates deduced by the homogeneous coordinate conversion theory. The effects of In order to improve the positioning accuracy and guiding accuracy of an airborne measuring device, a mathematical model of error analysis is established based on the coordinate conversion equation from geodetic coordinates to telescope coordinates deduced by the homogeneous coordinate conversion theory. The effects of some parameters in airborne measuring device on positioning result and guiding result are theoretically analyzed using Monte-Calro method. Several approaches to improve the accuracy of airborne measuring device are presented, such as improving the attitude accuracy and position accuracy of airplane. In addition, it is pointed that data processing is also an effective method to improve the positioning accuracy. The results indicate that positioning accuracy and guiding accuracy can both be increased by 30% through changing airplane attitude accuracy from 0.3°to 0.1°, and positioning accuracy can be enhanced by 9% through changing airplane position accuracy from 20 m to 5 m. The analysis process and result are useful for designing airborne measuring device..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 388 (2009)
Measurement and evaluation for profile tolerance based on images
WANG Zhong, CAO Jing-jing, ZHANG Li-kun, and ZHANG Jin
A profile measurement and evaluation method for the micro-parts based on the images is presented. This method includes the method of profile data modeling in theory, bound searching method of expansion polar angle corresponding theoretical points and evaluation method of least-deviation profile error. The evaluation meA profile measurement and evaluation method for the micro-parts based on the images is presented. This method includes the method of profile data modeling in theory, bound searching method of expansion polar angle corresponding theoretical points and evaluation method of least-deviation profile error. The evaluation method of least deviation profile error and classical least -square profile error are analyzed and compared based on several examples. The experiments on actual image show that the iterative times of the least deviation method are 0~3 fewer and the accuracy are 4%~12% higher than that of least-square method,which can meet the requirements of high accuracy and fast profile tolerance measurement of micro-parts..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 395 (2009)
Aircraft recognition based on affine transform
LI Xing-tang, CAO Li-hua, and WANG Si-wen
In order to recognize the type of aircraft in digital image fastly, an algorithm of aircraft recognition based on the structural feature points and affine transform is presented after the closed outline of an aircraft has been obtained. By using the symmetry of the aircraft to get the feature points and taking those poIn order to recognize the type of aircraft in digital image fastly, an algorithm of aircraft recognition based on the structural feature points and affine transform is presented after the closed outline of an aircraft has been obtained. By using the symmetry of the aircraft to get the feature points and taking those points as matched points of two different images, the homogeneous matrix between the two images is calculated; then by transforming the outline of an aircraft in one image to the other image, the outlines of two aircrafts in the latter image is compared to judge whether the two aircrafts are the same type. The experimental results indicate that the recognition result can be given within 0.2 s,after the closed outline of aircraft is obtained,which can satisfy the C3I system requirements of high precision, rapid speed and stabilization..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 402 (2009)
Super-resolution reconstruction method of image registration
QIN Feng-qing, HE Xiao-hai, CHEN Wei-long, WU Wei, and YANG Xiao-min
In order to improve the precision of registration algorithm and the quality of reconstructed image, an image registration method with sub-pixel precision is proposed,and super-resolution reconstruction is performed through iterative back projection algorithm. Firstly, an image registration method based on three-parametIn order to improve the precision of registration algorithm and the quality of reconstructed image, an image registration method with sub-pixel precision is proposed,and super-resolution reconstruction is performed through iterative back projection algorithm. Firstly, an image registration method based on three-parameter model is introduced. Then, an image registration algorithm based on four-parameter model is proposed. Because the rotation angle is not directly included in the movement model, the hypothesis of small rotation angle in Taylor series expanding in original method is avoided effectively. Finally, according to the movement information with sub-pixel precision gained by registration algorithms, super-resolution reconstruction is performed with iterative back projection algorithm. The experiments on simulated and real low-resolution images with big movement are carried out respectively,and the results indicate that proposed image registration algorithm obtains a higher reconstruction precision. The average translation error is reduced by 0.026 1 pixels and the average rotation angle error is decreased by 0.356 4°. The reconstructed image has better visual effect and the average PSNR is increased by 0.75 dB. These results show that proposed method can be used in the large multiple super-resolution reconstruction of low-resolution images with translation and big rotation, and can meet the requirements of practical application..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 409 (2009)
Improved immune algorithm for image restoration
ZHANG Yu-dong, and WU Le-nan
In order to improve the performance of super-resolution restoration for an image, a new model involving general white Gaussian distributed noise and anisotropy regularization is presented. To acquire the optimal solution of the new model, immune algorithm is proposed and improved in three aspects: a memory unit group iIn order to improve the performance of super-resolution restoration for an image, a new model involving general white Gaussian distributed noise and anisotropy regularization is presented. To acquire the optimal solution of the new model, immune algorithm is proposed and improved in three aspects: a memory unit group is introduced to make the algorithm perform on two independent groups parallelly; an adaptive method of exporting vaccines and inoculation is presented; and a chaos operator is implanted to the algorithm for anti-freezing. Analysis and experimental results demonstrate that the restoration based on this proposed model is robust both to different types of noises and to variances of noises. Moreover, the Improved Ratio of Signal to Noise(ISNR) of the restored image using this proposed model is 1.5 dB higher than that using traditional model. Meanwhile, improved immune algorithm can converge fastly,the steps of iteration are 8% that of the total steps for GA, and 40% that of the total steps for immune algorithm. The system consisting of the proposed novel model and improved immune algorithm is reliable on the super-resolution restoration..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 417 (2009)
Optimized design of real-time encode for aerial-video image
LI Shi, ZHANG Bao, and SUN Hui
An optimized design of aerial-video encode is presented to realize simultaneously real time compression for two PAL videos on an industrial embedded computer. The design chooses Discrete Cosine Transform (DCT) to decorrelate the image data. After comparing several kinds of fast DCT algorithms, AAN algorithm is optimizeAn optimized design of aerial-video encode is presented to realize simultaneously real time compression for two PAL videos on an industrial embedded computer. The design chooses Discrete Cosine Transform (DCT) to decorrelate the image data. After comparing several kinds of fast DCT algorithms, AAN algorithm is optimized and implemented, and the base of the optimization is presented. In addition, the search method of Variable-length Code (VLC) table is also optimized. By optimizing the two largest computational algorithm modules in the scheme, DCT and VLC table,a 768×576 color video frame can be compressed in 8 ms with P4 3.0G CPU. Under the compression ratio of 32∶1, the Peak Ratio of Singnal to Noise(PSNR) of the design reaches 29.47, which is extremely close to the performance of the wavelet algorithms, so it guarantees the decoding quality of image. The experimental results show that the design reaches a better balance among compression speed, compression ratio and compression performance in video encoding, and it can satisfy the requirements of the aerial-video compression..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 426 (2009)
Relationship between stereo depth and parallax image captured in stereoscopic display
WANG Ai-hong, WANG Qiong-hua, LI Da-hai, TAO Yu-hong, and LI Xiao-fang
In stereoscopic displays, stereo depth is associated with parallax in parallax image, and parallax is related with the layout of cameras when the parallax images are captured. In the paper, these cameras are laid in parallel configuration. By setting proper distance between cameras and shifting the images reasonably, tIn stereoscopic displays, stereo depth is associated with parallax in parallax image, and parallax is related with the layout of cameras when the parallax images are captured. In the paper, these cameras are laid in parallel configuration. By setting proper distance between cameras and shifting the images reasonably, the objects with a certain depth have zero parallax and the objects with other depth have expected parallax. The parallaxes correspond to different stereo depths, so the quantitative relationship between stereo depth and distance of two cameras for capturing the parallax images is obtained. An experiment is carried out to verify the theory, the results show that proposed quatitative relationship can help to take good parallax images for stereoscopic displays by laying out cameras suitably..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 433 (2009)
SIFT feature matching algorithm with global information
JI Hua, WU Yuan-hao, SUN Hong-hai, and WANG Yan-jie
An improved Scale Invariable Feature Transformation(SIFT) matching algorithm with global context vector is presented to solve the problems that SIFT descriptors result in a lot mismatches when an image has many similar regions. By detecting feature points in scale space, two kinds of feature vectors, a SIFT descriptor An improved Scale Invariable Feature Transformation(SIFT) matching algorithm with global context vector is presented to solve the problems that SIFT descriptors result in a lot mismatches when an image has many similar regions. By detecting feature points in scale space, two kinds of feature vectors, a SIFT descriptor representing local properties and a global context vector, are computed. Then, according to BBF searching strategy, the feature vectors are matched by using Euclidean distance. The experimental results indicate that the improved algorithm can describe feature points in a larger region,and can reduce mismatch probability of experimental images from 19% to 11% because global context vectors based on global shape information are induced to the SIFT vectors based local Information. These results reported above show proposed algorithm improves matching results greatly..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 439 (2009)
Data processing of hull deformation for spacecraft TT&C ship
LI Xiao-yong, ZHANG Zhong-hua, ZHU Wei-kang, XUE Guo-hu, and CHEN Gui-ming
To weaken the influence of hull deformation on the data of TT&C shipborne outer-trajectory measuring equipments, a hull deformation correction mathematical model is established. The basic structure, measurement principle and measurement elements of hull deformation measurement system are briefly introduced; Then, aTo weaken the influence of hull deformation on the data of TT&C shipborne outer-trajectory measuring equipments, a hull deformation correction mathematical model is established. The basic structure, measurement principle and measurement elements of hull deformation measurement system are briefly introduced; Then, a hull deformation measurement coordinate system is established,and relationship between deformation measurement angles and Euler’s angles is discussed; Finally, hull deformation data processing formula is deduced in detail and data processing mathematical model is presented. The engineering application results show that the influence of hull deformation on the semi-major axis “a” of spacecraft initial orbit is relatively greater. To near earth and near circular orbit, the influence value is in magnitude of hundred meters, whose maximum value is 800~900 m; and to big elliptical orbit, the influence can reach 20 km. However, the influence can be eliminated after correcting hull deformation. The established mathematical model reflects the objective law of hull deformation, which can be used to eliminate the influence of hull deformation on measurement data effectively and can improve data processing precision..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 445 (2009)
Analysis of image motion compensation accuracy for aerial push-broom sensor
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In order to analyze the effects of the speed,attitude and posture change of aircraft on the image quality of push-broom imaging sensor,an image motion model is established to calculate the accuracy of image motion compensation by combining light vector with optical axis revolution. The characteristics of image motion cIn order to analyze the effects of the speed,attitude and posture change of aircraft on the image quality of push-broom imaging sensor,an image motion model is established to calculate the accuracy of image motion compensation by combining light vector with optical axis revolution. The characteristics of image motion caused by translation and rotation are analyzed, and the image motion model of push-broom imaging sensors is established by decomposing the movement. With two groups of parameters, the influence of aircraft motion on image motion is analyzed and the method of image motion compensation is given. The accuracy of image motion compensation is calculated based on error budget of variable with Mont Carlo method .While the high-speed(v/H) ratio is 0.3 ~ 0.5 (1 / s) and the TDI stage is no more than 32,the 3σ value of image motion compensation (IMC) error is 16 μm,which can satisfy the requirement of remote sensor..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 453 (2009)
Target location method based on invariable moment feature matching
WU Gang, WU Chun-feng, HOU Qing-yu, and ZHANG Wei
In infrared imaging matching navigating system, the image distorted transformations between reference images and real-time images can increase the difficulty of imaging matching,for two kinds of images are taken unsimultaneously at different heights and different view points. Based on the basic principles of infrared iIn infrared imaging matching navigating system, the image distorted transformations between reference images and real-time images can increase the difficulty of imaging matching,for two kinds of images are taken unsimultaneously at different heights and different view points. Based on the basic principles of infrared imaging, effect of the difference in the ground resolution of infrared imaging on the invariability of invariable moment features is discussed in this paper. The expression of six-dimension invariable moment feature vectors of images in different ground resolutions is derived. Discussed results show that the feature vector is invariable for images in complex transformations on translation, rotation, noise adding and differences in resolution, and can be used as the features in the application of imaging matching location. The Camberra distance as the image matching metric between real-time image and reference image is proposed. The method is proved correct and feasible in experiment part..
Optics and Precision Engineering
- Publication Date: Sep. 21, 2021
- Vol. 17, Issue 2, 460 (2009)
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