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	Analysis of laser jamming to satellite-based detector (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Guo L.-H.; Guo R.-H.; Wang S.-W. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 The reconnaissance satellite communication satellite and navigation satellite used in the military applications have played more and more important role in the advanced technique wars and already become the significant support and aid system for military actions. With the development of all kinds of satellites anti-satellite laser weapons emerge as the times require. The experiments and analyses of laser disturbing CCD (charge coupled detector) in near ground have been studied by many research groups but their results are not suitable to the case that using laser disturbs the satellite-based detector. Because the distance between the satellite-based detector and the ground is very large it is difficult to damage it directly. However the optical receive system of satellite detector has large optical gain so laser disturbing satellite detector is possible. In order to determine its feasibility the theoretical analyses and experimental study are carried out in the paper. Firstly the influence factors of laser disturbing satellite detector are analyzed in detail which including laser power density on the surface of the detector after long distance transmission and laser power density threshold for disturbing etc. These factors are not only induced by the satellite orbit but dependence on the following parameters: laser average power in the ground laser beam quality tracing and aiming precision and atmospheric transmission. A calculation model is developed by considering all factors which then the power density entering into the detector can be calculated. Secondly the laser disturbing experiment is performed by using LD (laser diode) with the wavelength 808 nm disturbing CCD 5 kilometer away which the disturbing threshold value is obtained as 3.5510-4mW/cm2 that coincides with other researcher's results. Finally using the theoretical model the energy density of laser on the photosensitive surface of MSTI-3 satellite detector is estimated as about 100mW/cm2 which is largely exceed the disturbing threshold and therefore verify the feasibility of using this kind of laser disturbing the satellite-based detector. According to the results. using the similar laser power density absolutely saturate the requirements to laser disturbing satellite-based detector. If considering the peak power of pulsed laser even decrease laser average power it is also possible to damage the detector. This result will provide the reliable evidences to evaluate the effect of laser disturbing satellite-based detector. 2009 SPIE.
	Resolution performance of extreme ultraviolet telescope (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Yang L.; Chen B.; Chen B.; Liang J.-Q.; Ni Q.-L. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Extreme Ultraviolet Telescope (EUT) will image solar corona in four EUV narrow bandpasses defined by multilayered coatings deposited on normal incidence optics. In order to make sure it will get sub-arcsecond angular resolution in the mission we have to test its resolution performance on ground. The EUT is aligned by Zygo interferometer first and a global wavefront error of 0.152 peak to valley is obtained ( = 632.8nm ). Because of the difficulty of angular resolution test for EUT at its operating wavelengths we test its optical performance at visible and UV band. The method is to place the resolution test-target on the focal plane of collimator and illuminate the target by visible and UV light espectively then the collimated light will go through EUT and image at focal plane on CCD. By analysis of the images obtained in experiments we conclude that the angular resolution of EUT is 1.22 at visible light ( = 570nm ) which is very close to diffraction limit (1.20) and according to these results we estimate that the operational wavelength resolution is better than 0.32 meets design requirements. While for UV light the angular resolution is 1.53 that is different from diffraction limit (0.53) the error comes mainly from large pixel of EUV camera. 2009 SPIE.
	Design of high-resolution fourier transform lens (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 With the development of optical information processing high-resolution Fourier transform lens has often been used in holographic data storage system spatial filtering and observation of particles. This paper studies the optical design method of high-resolution Fourier transform optical lenses system which could be used in particles observation and holographic data storage system. According to Fourier transform relation between object and its frequency plane and the theory of geometrical optics the system with working wavelength 532nm and resolution 3 m was designed based on ZEMAX. A multi-configuration method was adopted to optimize the system's lenses. In the optical system a diaphragm was placed at the system's spectrum plane and the system demanded a low vacuum to cut down the influences of atmosphere and other particles. The result of finite element analysis indicated that the influences of vacuum pumping to optics spacing and mirror surface shape very minor and the imaging quality not being affected. This system has many advantages such as simple structure good image quality and a high resolution of 3 m. So it has a wide application prospect and can be used both in holographic data storage system and particles observation.
	Research on the support structure of the primary mirror of large-aperture telescope (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China Yang W.; Jingxu Z. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 Large-aperture telescope can be used in surveying battlefield researching landform searching object real-time monitoring imaging detecting and identifying spatial targets and so on. A large-aperture telescope for achieving high resolution power is designed to monitor spatial target and image in real time. Real-time monitoring plays an important role in military conflicts. The orbit parameter of object quantity geometrical shape parameter and so on can be obtained by detect spatial target. With the development of optical technology people require larger aperture in optics-electronic (OE) system. By increasing optical aperture the ability of collecting light and resolution power in the system can be enhanced. But the support structure of the primary mirror of large-aperture telescope will be a very difficult problem. With the increase of primary mirror aperture the weight of the primary mirror will become larger than before. The root mean square (rms) of the primary mirror is affected by many factors such as deadweight deformation of heat environment and so on. Due to the primary mirror of telescope is an important component of telescope system. By reducing the weight of primary mirror precision of the system is ensured. During the designing phase one can consider the supporting project of the primary mirror synthetically and analyze it roundly according to technical requirement of optical system and the effect factors. The final structural design can be reasonable. In an astronomical telescope the surface of reflector is an important part for collecting dark radiation of celestial bodies. Its surface shape will have an effect on collecting efficiency of telescope radiant energy directly. So the rms must be very high. Optical system of large aperture small wavelength and small focus can receive maximal light intensity. For ground-based optical astronomical telescope the design proposed in the paper can satisfy the requirement of the possible minimum atmosphere seeing at astronomical observatory site and exert the use efficiency of the telescope adequately. So the accuracy of the traditional surface of reflector can assure that 90% of all the light energy can be focused on within the angle diameter range of the minimum atmosphere seeing then 100% of light energy should be focused on the angle diameter range of minimum atmosphere seeing. Because the rms of mirror is very high precise surface machining and accurate the support of mirror are very important tasks during designing and manufacturing the telescope. In the paper various support techniques of a large-aperture telescope primary mirror are discussed and a 3.5 meter telescope system at the Starfire Optical Range (SOR) overviewed simply which was operated by the Directed Energy Directorate of the Air Force Research Laboratory Kirtland AFB NM USA from the ground-based O-E system for the observations of spatial target. We also analyze Theoretical elastic deformation of the Steward Observatory 2.3 meter mirror is analyzed.
	A novel method of calculation-separating second order spectrum in grating spectrometers (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China 作者: Xiang Y. 收藏 \| 浏览/下载：15/0 \| 提交时间：2013/03/25 In grating spectrometers according to wavelength short-wave second-order spectrum superimposes on long-wave spectrum with the wavelength twice as long as the short-wave. Usually spectrum of long-wave range is got via preventing the superimposition of short-wave second-order spectrum by cut-off filters. This paper analyses the characteristic of the ratio of short-wave second-order spectrum in long-wave superimposing spectral range to first-order spectrum in short-wave free spectral range of diffraction gratings. The paper studies a novel method of obtaining long-wave spectrum via calculation-separating short-wave second-order spectrum from mixed spectra in long-wave superimposing spectral range by data processing with the spectrum of free spectral range and the ratio (instrumental parameter) of short-wave second-order spectrum to first-order spectrum measured beforehand. Spectrum-measurement experiments were carried out by VIS-NIR spectrometers (0.36 - 1.0m). That the spectrum data got via calculation-separation coincide with those got via cut-off filter indicates that spectrum can be obtained by processing the measured date without filters in whole operating wavelength.
	Theoretical analysis of 980nm high power Vertical External-cavity Surface-emitting Semiconductor Laser (VECSEL) (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wang L.-J.; Wang L.-J.; Ning Y.-Q.; Qin L. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 By using bottom-emitting structure we will develop laser diode (LD) pumped 980 nm VECSEL with active region of InGaAs/GaAsP/AlGaAs system. Because the thickness of barrier layer and absorption layer exceed that of quantum well single well approximation model (KP method) can be used to calculate the band structure of VECSEL. The Schrodinger equation of finite deep potential well can be adopted to calculate the energy level structures of electron heavy and light holes. According to the transition selection rule we theoretically obtained the emitting wavelength of VECSEL and calculated quasi-Femi energy of valence band and conduction band based on the analysis of energy level structure of electron and holes. By analyzing the gain of strained quantum wells we calculated the gain of VECSEL using transition matrix elements of electron heavy and light holes. We give out the threshold gain output power and other characteristic parameters. We will study the configuration of VECSEL and pumping scheme. We designed external cavity mirror active region and bottom-emitting structure. A LD-pumped vertical external cavity surface-emitting laser whose output power is greater than 1.0 W can be predicted.