2004 Vol. 25, No. 6

Application of Regenerative Feedback Technology in Tracking Control System
WANG Xiao-qi, ZHAO Zhen-hai, LI Jing-di, LI Guang-liang
2004, 25(6): 1-4.
With the state-of -date computer-aided control technology,in which the coordinate transformation and retransformation,the digital calculation and filtering/regenerative compensating calculation are carried out,the compound control-tracking system with regenerative feedback is built up and the high-precision tracking to high-speed moving objects is finally realized.The technology used in one of the national key projects was proved to be ideal by the land and sea tests,can be used in tracking systems for tracking various moving objects and can effectively improve the tracking accuracy of tracking systems.
Theoretical Study
Study on the Near-Field Optical Storage Property of Bacteriorhodopsin
FENG Xiao-qiang, YANG Wen-zheng, BAI Yong-lin, HOU Xun, YANG Qing, CHEN Feng
2004, 25(6): 5-8.
With near-field optical microscope,the static photochromic property of BR-D96N film is investigated based on its transition between B State and M state.The results show that in the near-field area of BR film,it has strong absorbance to red light before excited by green light,but not after excited to M state,and BR can relax to B state when there is no exciting light.This near-field property of BR is similar to that of far-field,having special character of photochromism and relaxation,and BR is expected to be used as high-density optical storage media and micro-devices of optical information processing.
The Analysis and Study of Multiple-sampling of CCD in the APT Technology of Optical
ZHANG Wen-tao, ZHU Bao-hua
2004, 25(6): 9-11.
It is the method of pulse count that can be used to carry out the optical detection with CCD,and it is said that each pulse denotes a pixel,so the detective resolution only have one pixel.Although the detecting resolution can be enhanced by increasing the amplification and diffraction radio,the detective resolution only achieve micron level,since the existence of the aberration,spherical aberration effect,In order to improve CCD's detective resolution ulteriorly,a new method of multiple-sampling is brought forward in this paper,With the method,the detective resolution can be raised to the level of sub-pixel.
Optical Design
The Optimal Approximation for the Pattern Formed with Fresnel Zone Plate Antenna
JIANG Ze, DU Hui-ping
2004, 25(6): 12-15.
With the view of the optimal approximation for the formed beams.the radiation pattern and the field distribution in the focus zone of Fresnel zone plate antenna approximation with the fields of the linear array have been studies based on the methods of weighted residue and Prony,which suit for the approximation for the real patterns of various Fresnel zone focusing configuration.The work for the design of the linear array with high performance is crucial,as well as promotes the penetrating into the mechanic investigation of the Fresnel zone focusing configuration farther.
Laser Technology
Development and Application of Ultrafast Pulse Fiber Laser
HUANG Xiu-jiang, LIU Yong-zhi, SUI Zhan2, LI Ming-zhong, CHEN Hai-yan, LIN Hong-huan
2004, 25(6): 16-21.
Ultrafast pulse fiber laser is now one of the most active subjects in the field of the laser research,and it will have a wide application for sure.Development of ultrafast pulse fiber laser is introduced in this paper.The principles and critical technology of ultrafast pulse fiber laser are discoursed.Several new methods are compared.The trend and applications of the ultrafast pulse fiber laser are analyzed.
The Polarization Property of Tapered Fiber
XIAO Zhi-gang, ZHU Sheng-xiang, XUE Chun-rong
2004, 25(6): 22-25.
Polarization properties of tapered fiber are discussed fiber are discussed in this paper.By the Maxwell equation and boundary condition,the field distribution of ideal fiber is analyzed and the transmission property of the fiber is also explained.Further more.geometric optics treatment is convenient due to the relation between the length of tapered fiber and its polarization property.Through the experments and analyses,we may draw the conclusion that the elliptic polarization light is obtained when linear polarization light transmits through the single mode fiber or after coupling.
Research on Displacement Measurement Based on Bragg Gratings
LI Zhi-quan, CAI Lu-lu, GAO Qing, WU Fei
2004, 25(6): 26-30.
This paper presents a method of the displacement measurement using the technology of fiber Bragg gratings.After a broadband light source passes through separate Bragg grating,the synthesized light source,which a temperature stabilizer controls the stability of wavelengths,is obtained.The synthesized wavelength is longer than those of conventional light source,so the permitted measured range of path-length is enhanced by several hundred times.the measuring accuracy of the interferometer is improved because of the wavelength accuracy of fiber Bragg gratings.Inaddition,a M-Z interferometer used for high precision displacement measurement proves that this system with simple structure can complete the high-precision measurement.
The Correlation Study of Channels in Horizontal Multi-beam Atmospheric Communication
LIU Wei-hui, WU Jian
2004, 25(6): 31-33.
On the basis of Kolmogorov theory,the physical meaning of beam correlation function on receiving plane is extended.Based on the correlation analysis of multiple beams crossing over the atmosphere.The analytical solution formula of the light-intensity oscillation variance of multiple beams is deduced.The result shows along with the spacing increase of channels,the channel correlation decreases,and so does the oscillation variance.When the channels overlap completely,the light-intensity oscillation variance of multiple channels is no difference from that of one channel.
Infrared Technology
The Unitormity and Linearity of Infrared Spectral Response of Decector
ZHAN Chun-lian, LI Yan-mei, LIU Jian-ping, LI Zheng-qi
2004, 25(6): 34-37.
The Uniformity and linearity of spectral response of infrared detector are considered as the important parameters to evaluate the characteristics of infrared detectors,The Optic Metrology Station is currently engaged in a programme of work to Measure the uniformity and linearity of response of infrared detector.which includes some work in the atmospheric windows,and the Station also busy with the evaluation for some commercial infrared detectors,which are expected to beidear detectors and to be used to transfer the infrared spectral responsivity.The paper described the facilities.measuring methods and results,and evaluated some infrared detectors working in different wave ranges to transfer quantity value.
Reaearch of the MRTD Mathematical Model for Thermal Imaging System
LI Xu-dong, AI Ke-cong, ZHANG An-feng
2004, 25(6): 38-42.
The history and achievements on the minimum resolvable temperature difference(MRTD)mathematical model are researched.The most representative ten kinds of MRTD equations are transformed and deduced.The inherentrelations and difference of these equations are analyzed.Based on the match filtering model,the new MRTD equation,in which the too much approximately sampling is eliminated,tree dimension noise model has been described completely,and the effect of scan effenciency and over scan ratio has been included in the spatial integral of eye/brain,is deduced.
Opto-electronic Device
Application and Development of Optoelectronic Sensors Mounted in Battlefield Reconnaissance Vehicles
YANG Hai-cheng, LIN Guo-cun
2004, 25(6): 43-46.
The paper discusses the application and development of optoelectronic sensors for battlefield recce vehicles.All kinds of sensors are analylized and compared.Our view point about the application of multispectral technology,image fusion technology of multisensors and masts is given.
Progress in Optical Current Transducer Technique for Power Systems
JIAO Bin-liang, ZHENG Sheng-xuan
2004, 25(6): 47-53.
The technology of the optical measurement of current is reviewed.Several different approaches being developed and their principles are described.The major problems of these approaches and their probable solving methods are discussed.At the present stage,bulk glass transducer technology is more mature than others and some commercial products have been developed.The hybrid transducer has a higher accuracy but the active circuit in its sensing head involves a complicated power supply problem which has not been solved completely.The all-fiber typeis the developing goal of optical current transducer and its main problem at present is the linear birefringence in sensing fiber.This problem is dependent on the further development of new fiber material and integrated optical devices.Finally,the developing trend and the commercial prospects of optical current transducers are analyzed.
Development of a Test Software for the Modulated Transfer Function of CCD Camera
GUAN Ying-zi, HAN Si-ning
2004, 25(6): 54-56.
Fourier analysis method is often used to measure the modulated transfer function MTF results quickly.And for this reason,the software for testing the optical transfer funcyion of CCD camera is developed based on the knife-edge scan method,With this software,digital image files obtained by CCD camera can be read in,the noise among the data can be filtered and the position of the knife-edge can be auto-identified then the suitable area can be chosen to calculate the optical transfer function of the CCD camera.This software,which has a favorable user's interface,is developed with Visual C++and can be operated conveniently.The calculated results can be outputted as both list and format.Our testing results are consistent with those gotten from Russian software.
Obtain the Relative Displacement of the Fringe-centerlines in the 3-D Profilometry Measurement Using Grating Projection
HUANG Yan-qun, TIAN Ai-ling
2004, 25(6): 57-60.
It's important to accurately the relative displacament of the fringer-centerlines in the 3-D profilemetry measurement technology using the triangle method.The method of barycenter,which can obtain the sub-pixel accuracy to abstract the finge-centerlines and tracking its direction with the template technology,the relative displacement of the fringe-centerlines being relative to the reference fringe-centerlines can be obtained.