2004 Vol. 25, No. 5

The Application and Present Situation of Lasers in the Automobile Industry
WANG Yong-gang, MA Xiao-yu
2004, 25(5): 1-2.
Some important applications of lasers in automobile.The development of lasers are discussed such as laser welding,laser marking,laser heat processing,laser cutting and so on.Types of lasdrs used in automobile in dustry are classified.In the end,the application prospect of all solid-state laser pumped by semiconductor laser and ultrashort pulse laser are described.
Theoretical Study
Study on Fizeau OPtical Synthetic Aperture Paraxial Imaging
WANG Zhi-le, ZHANG Wei
2004, 25(5): 3-6.
Proceedings from the theory of geometric optics,the condition adaxial noncoherent imaging of Fizeau opticalsynthetic aperture imaging system is derived to achieve diffracion limited performance over a finite field of view,and the conclusion is that the angular magnification of the individual telescope must be equal to the linear demagnification factor.So telescope with a special aperture diaphragm so as to teproduce exactly the ensemble of a collecting telescope.Then,the constraint to Fizeau optical synthetic aperture imaging system is achieved.
Sellmeier Coefficients for the Refractive Indices of Calcite at Crystal Different Temperatures
LI Hong-xia, WU Fu-quan, FAN Ji-yang
2004, 25(5): 7-10.
The refractive index of the calcite varies with the wavelength.With strict solution,the thesis gains the expression of the corefficient for the sellmeier equation.It agrees with the experimental results well.The expression of the thermo-optical coefficients at the different Wavelengths are got by linear interpolation aloorithm.And it can yield the refractive indices of the calcite at different temperature and different wavelengths through it.Then those can get the constants of the equation at different temperature.
Wavelength Assignment Algorithms of WDM Wavelength Routing Optical Network
LI Yong-jun, LI Wei-min, WANG Hong-gang
2004, 25(5): 11-15.
In WDM optical network,wavelength is the unit of transmission and switching.which is the limited network sources,so the research of wavelength assignment algorithm becomes a focal topic,With efficient algorithm,the utilization factor for wavelengths can be improved greatly and the bandwidth resources in WDM can be made full use of.Several static and dynamic wavelength assignment algorithms are presented in detail.Especially to larger mesh networks,several kinds of dynamic wavelength assignment algorithms are introduced.For the usage of wavelength converter,a layered-graph approach,is put forward,which can soluve routing and wavelength assignment simultaneously,is put forward and is fit for random wavelength converters and WDM optical network.
The Research of Rotatory Apparatus with Compound Wave Plates
LIU Yan, LI Guo-hua
2004, 25(5): 16-17.
The theory of rotatory apparatus with compound wave plates is analysed by using the matrix optics.The condition of the compound binary wave plate and ternary wave plate rotatory apparatus and the mathematic expressions of the magnitude of ratatory angle are gived.A example of application is also gave.The result shows taha the magnitude of roratory angle relates to the retardation of every wave plates and the included angle between their fast axes and X axis.
The Research of Calibration of Radiometers
WANG Xue-xin, YANG Zhao-jin, YUE Wen-long, YAN Xiao-yu
2004, 25(5): 18-21.
The calibrations of radiometer is a technology that is taken primary source and a absolute radiometer primary radiometer as a highest standard.It calibrates standard detector by this standard,then using this standard to calibrate common detectors.The basic equipment for radiometic calibrating is a set of standard radiometer and primary standard source.In this paper,we introduce the fundamental principle of the calibrating a detector with the standard radiometrer and discuss is the selection of the working standard for increasing the spectral resolution.By discussing the above problem,we expect to resolve how to select the best detector and source.we make a list of of all possible detectors or sources and their features to make sure source and detector are the best.
Night Vision
A Research into the Effect of Funnel MCP on the Relationship Between Current Gain and Noise Figure
FU Wen-hong, CHANG Ben-kang
2004, 25(5): 22-24.
The principle of photon scatter and electron scatter of MCP is describad.The method of improving the open arearatio and reducing the noise of MCP from enlarging the input end of the channel is presented.A mathematic model of funnel MCP is built.The theoretical evidence of reducting noise figure and improving the current gain is given.It will provide a theory foundation for further craft research.
Microchannel Plates and Its Main Characteristics
PAN Jing-sheng
2004, 25(5): 25-29.
The working principle of microchannel plate(MCP) is described briefly.The main performance characteristics and its working parameters are introduced,including thickness,open area ratio,gain uniformity,dynamic range,working life and resolution etc.The relationship between these performances characteristics and parameters is presented.On the basis of the presentation mentioned above,a specific relationship and factors,which affect parameters,is analysed.The further understanding and processing of the relationship between MCP's main characteristic performances and parameters are more significant for the MCP's production and application
Effect of Tube Making Technique for Generation III Low-light-level Image Intensifier on Photoemissive Property of photocathode
XU Jiang-tao
2004, 25(5): 30-32.
The effect of the tube making Technique on the photoemissive property of the photocathode is described.The technical quality of the cathode assembly preparation and the cathode activation is detected on line with the analytical instruments and the method of optical detection.The result shows that the main factors,which affect the technical quality of the cathode assembly preparation,are surface oxidization of emissive layer,impurity pollution,doped concentration nonuniform,less variation of doped concentration gradient,the sticking stress of GaAs and glass,and the main factors,which affect the cathode activation,are the degree of vacuum for activation at lower than 8x10-8Pa,the partial pressure of H2O,CO,CO2 and C in the vacuum residial gas at higher than 10-8 Pa and the improper caesium and oxygen refining.With a method of the transmission-reflection luminance,we also found that the pinholes,cracks and atomization on the surface of the emissive layer are the key factors that might cause the lower emissive property of the photocathode.
Laser Technology
The Study for Laser Beam Transmission Character in Atmosphere Rondom Channer by Using CCD
ZHANG Wen-tao, ZHU Bao-hua
2004, 25(5): 33-36.
Some effects that affect the transmission in atmosphere of laser signals are introduced.Some phenomena,such as the absorption,dispersion and onflow of aerosol,dust,frog,rain and haze,are engendere by the interaction of laser and atmosphere when the former goes through the latter.These all will produce some other effects that would strongly affect the transmission of laser signals,especially attenuation,coruscation and dithering of beam.They can be experimentally validated through a set of device besides CCD that can shoot and analyze the images of laser signals on conditions of different visidility,atmosphere and time.
Fiber Optics
The Application of the laser Fiber Gyro Lens in Utrashort Pulse Measurement
ZHANG Zhe-huang, CAI Feng-yi, QIN Xiao-dong
2004, 25(5): 37-39.
The applied theory of the measurement on ultrashort pulse width shape and phase with a laser fiber gyro lens is introduced;By using the fiber gyro lens as a optical delay line which can adjust rotating angular velocity automatically,we can realize the arbitrarily continuous adjustment of rotaing angular velocity.With the normalized algorithm of Gerchberg-Saxton,we can realize the process control automation.In this way we overcame the shortcoming of low veracity and limited precision caused by fixed time-delay;By using the single-photon counter system to test the envelope of coherent light,the precision improved greatly.THe application foreground on physics,biology,chemistry and overspeed optic communication is widened by the research.
A Scenario of the Magneto-Optical Current Sensor for Large Dynamic Range Measurement
JIAO Bin-liang, ZHENG Sheng-xuan, SHAN Wei
2004, 25(5): 40-42.
A new method to extend the dynamic range of the magneto-optical current sensor is presented.The magneto-optical current sensor is based on Farada effect and Ampere's law to realize the current measurement.Because the Faraday rotation angle increases periodically with the current measured,only a monotone region of the sinusoid could be used and the measurement range is narrowed.With the wavelength dependence of the Verdet constant,a large current could be measured by wayof measuring the difference of the rotation angles corresponding to the two different wavelengths within one sensor.The metering data,which is more accurate than the data from the dual wavelength.can be acquired by a single wavelength.It is theoretically shown that 20% Verdet constant difference between the two wavelengths will increase the current measuring range 6 times.This method can make the magneto-optical current sensor adaptive to both metering and protection in power system.
The Study of the Resonant Wavelengths of Long-period Fiber Grating with Langmuir-Blodgett Thin-film Overlay
YE Mei, FENG Xian-qun, YE Hu-nian
2004, 25(5): 43-46.
This paper theoreticall analyes spectral characteristics of the resonant wavelength of long-period fiber gratings varying with the change of the ambient refractive index in detail.The analytical results agree with the relationship between the thickness of the film and the resonant wavelength of long-period fiber grating with Langmuir-Blodgett thin-film overlay well.
Image Processing
A Dual-channel Night Vision Color Image Fusion System
TAO Qian, GUO Hong, WANG Ling-xue, WANG Xia, JIN Wei-qi
2004, 25(5): 47-50.
A dual-channel night vision color image fusion system is presented.The system uses a Matrox Meteor-II/multi channel image card to realize low-light-level/low-light-level and infrared/low-light-level image fusion processing.Image fusion processing of MIT,BIT,TNO,Linear combination and mixed structure is adopted.With the image card's image processing function library.The color image fusion processing was realized was readlized in MS VC++6.0 environment.Based on the prototype system being built,evaluation and further research on color night vision image fusion algorithm could be implemented.
A Method for Automatic Identification of Dots on Films
TANG Hui-jun, WANG Jian-jun, LUO Xiu-juan, ZHOU Si-zhong
2004, 25(5): 51-52.
The image quality of films taken by high-speed cameras is affected by shooting,developing and storing status.Recognization of matrix dots on poor quality films using traditional threshold method brings dots misread.In this paper,we present a concise method for automatic dot recogniaztion of dots on poor quality films.By using contrast and space criterions,and discussing parameters relative to them,the accuracy of dot recognization is increased.With this method,the fram recognition error rate is better than1/1000.
Thin Film
The Optical Properties of TiO2 Thin Film Prepared by Electron Beam Evaporation
PAN Yong-qiang, ZHU Chang, MI Qian, SONG Jun-jie
2004, 25(5): 53-55.
The optical properties of TiO2 thin film prepared by electron beam evaporation with different craft parameters are studies.On the base of experiments,the main factors of affecting the refractive index of the TiO2 thin film deposition assisted by ion beam have been found out.Function relation of TiO2 refrative index,oxygen pressure and deposition speed have been gained,besides infrared spectrum.Refractive indices of TiO2 thin film deposited in ioned and molecular oxygen are compared.
Study of the Reasonableness of Fitting Model Concerning DLC Film Optical Constant
LI Jian-chao, SU Jun-hong, XU Jun-qi
2004, 25(5): 56-59.
The measurement results of spectroscopic ellipsometry(SE) can not directly reflect the structure and optical properties of the tested samples,so the least square method for fitting the measurement data is needed,and the interpretation of the SE results is model dependent.Usually the fitting results are not only one.Thus,taking into account of the reasonableness of fitting model is important.The reasonableness of the model constant of the DLC film's optical constant is studied with the ellipsometry in this paper.We analyzed and fit the optical constant of the DLC film deposited by pulseion source,and investigated the reasonableness of the fitting model and reliability of the fitting result.
Testing Technology
Research on Testing Image Transfer Signal-to-Noise Ratio of Image Intensifer
ZHOU Bin, LIU Bing-qi, MAN Bo
2004, 25(5): 60-61.
The image transfer signal-to-noise ratio isan important parameter which can characterize the combination property of image intensifier all-roundly and quantitatively when detecting the weakly radiative image.It has the important significance for determining the detection sensitivity threshold of image intensifier.Based on its test principle,a highly sensitive and low noise CCD is adopted as the output image detector and the digital image processing technology is introduced.The automatic test of image transfer signal-to-noise-ratio of typical target is realized by using a test system we designed.The experimental results getting with several test show that the test process is automatic and fast and the tested data is accurate and steady.The uncertainty is below +-3% in the same test condition.
Simulation Calculation of Measuring Optical Aspheric Surface Based on Light Pattern Projection
DUAN Cun-li, TIAN Ai-ling, CHEN Zhi-chao
2004, 25(5): 62-66.
In this thesis,the fundamental of optical projection measurement for aspheric sureface is explained,the simulation calculation with computer is put forward and the aim of simulation is defind.We choose the reference sphere fitting into asphere,educed the calculation expressions of the vertical axis distance and measured the distance in the reception screen according to the optical theory and math formula.And also we simulated the vertical axis distanced with C Programme and obtained the simulation asphere curve using excel.The simulation caculation result is in accordiance with the theoretical calculation and meets the accuracy of +0.001um.