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	Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文 OAI收割 2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：61/0 \| 提交时间：2013/03/25 The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope the structure should have high stiffness and high reliability and light weight. Compared with invar aluminum alloy and titanium alloy carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages such as ultra-light weight high stiffness and dimensional stability etc. The optimization method and the baffle design can be helpful to other coaxial telescopes such as Cassegrain Gregorian and their subdivisions. 2012 IEEE.
	Computer simulation of thermal focal length of laser crystal and thermally-near-unstable resonator 会议论文 OAI收割 2012 9th International Conference on Fuzzy Systems and Knowledge Discovery, FSKD 2012, Chongqing, China, MAY 29-31, 2012 作者: Geng AC(耿爱丛); Li BH; Chen XB; Yang XD; Yang MJ(杨明江) 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/02/26 Computer simulation Fuzzy systems Lasers Gain medium High beam quality High order mode High output power Laser crystals LD side-pumped ND : YAG lasers Output power Pump power SIMPLE method Theoretical prediction Thermal focal length
	Design and simulation of CMOS star sensor lens with large relative aperture and wide field (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China Zhong X.; Jin G. 收藏 \| 浏览/下载：60/0 \| 提交时间：2013/03/25 A 50mm focal length F/1.25 Gaussian type optical system is designed in this paper which has 20field of view. Actual star image adding optical cross-talk effect of CMOS(Complementary Metal Oxide Semiconductor) detector is simulated by non-sequential ray tracing in ZEMAX optical design and analysis software to evaluate its performance. The distortion relative to image spot centriod is introduced and calculated by simulated star images which is less than 0.03% of lens in this paper. Thermal adaptability is discussed by opt-mechanic thermal analysis which shows the RMS spot radius of marginal filed changes less than 0.7m under 10C temperature gradient and changes less than 1m during homogeneous temperature changing from 40C to 40C. The results of analyses and simulations show the design of this lens can achieve the requirement of high precision CMOS star sensor well. 2011 IEEE.
	Design of reimaging F/1.0 long-wavelength infrared optical system (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 A reimaging F/1.0 long-wavelength infrared optical system is proposed. The design has a flexible opto-mechanical layout. The design process is as follows. Firstly the catadioptric reimaging system consists of two reflecting mirrors and a relay lenses. Two reflecting mirrors make up of the first imaging system and are therefore free of chromatic aberrations while low dispersion lenses were used in the reimaging system so the optical system do not need achromatic design for a high image quality. Then to correct high-order aberrations resulting from large relative aperture more parameters need to be used with aspheric or diffractive surfaces due to modern optic technology development. Here aspheric is selected for easily manufacture. Finally the design is completed with the help of ZEMAX software. The effective focal length of the objective is 120mm and the field of view (FOV) is 4. The simulated final design shows adequate image quality and the modulation transfer function (MTF) is close to diffraction limit. The effect of the surrounding environmental temperature is analyzed using the concept of thermal defocusing and the thermal compensation is discussed. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Structural design for lightweight off-axis TMA space telescope (EI CONFERENCE) 会议论文 OAI收割 2011 2nd International Conference on Digital Manufacturing and Automation, ICDMA 2011, August 5, 2011 - August 7, 2011, Zhangjiajie, Hunan, China 作者: Li Z.; Li Z. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 A kind of small space telescope with 1m focal length was designed. By adopting finite element analysis technique the structure of the space telescope was analyzed. The analysis results indicate that the surface profile accuracy of the mirrors reach to RMS 8.0nm with the working circumstances 4C uniform temperature change and space micro-gravity the base frequency of the structure was 115 Hz. It shows that the designed structure has sufficiently high dynamic and static stiffness and thermal dimensional stabiLity. This space optical telescope is very suitable for little satellite application. 2011 IEEE.
	Design of the infrared dual-band athermalized optical system based on HDE (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Infrared Imaging and Applications, June 17, 2009 - June 19, 2009, Beijing, China 作者: Zhang L.; Sun Q.; Wang H.; Wang H.; Wang H. 收藏 \| 浏览/下载：97/0 \| 提交时间：2013/03/25 A dual-band infrared optical system adopting an uncooled LW infrared detector and a cooled MW infrared detector is designed and manufactured while in the LW IR band the F/# is 1 and the focal length is 114 mm based on the athermal ability and special diffractive properties of harmonic diffractive elements. The design shows in the MW IR band the F/# is 2 and the focal length is 72 mm for the temperature range -40 70 the MTF value is over 0.5 at 10 lp/mm. Finite element method is applied to the opto-mechanic structure of the system for thermal analysis for the temperature range -40C 70C the MTF value is over 0.4 at 20 lp/mm which confirms the imaging ability of the system in a wide temperature range. 2009 SPIE.
	High power red laser at 671nm by intracavity frequency doubling of a nd : yvo4 laser 期刊论文 iSwitch采集 Chinese physics, 2005, 卷号: 14, 期号: 7, 页码: 1433-1438 作者: Yao, AY; Hou, W; Li, HQ; Bi, Y; Li, RN 收藏 \| 浏览/下载：25/0 \| 提交时间：2019/05/09 Quasi-continuous wave Double-end-pumped Thermal focal length
	Study on LD-pumped Nd:YAG laser cutter (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Zhang G.; Zhang G.; Zhang G.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 The theory of laser cutter and the technology neck is analyzed. We can conclude that it is almost impossible to deal with the waste thick silicon wafers which are yielded in producing silicon wafers by conventional eroding or diamond cutting when the cutting velocity equals 100mm/min while it is also unperfected with ecumenical laser cutter without good beam quality or precise laseroptics system. It is represented that high average power and high repetition rate laser with good beam quality and precise laseroptics system are pivotal to obtain excellent cutting effect such as thick groove depth double-layer 0.75mm thick silicon wafer can be penetrated.. The cross section is fine and the groove is narrow rapid cutting speed the cutting quality meets the expecting demand. fine kerf section without considering the effect of technique. Considering laser medium thermal lens effect and thermal focal length changing with pumping power using plano-convex high reflectivity mirror as the back cavity mirror to compensate the heat lens influence a /4 waveplate to compensate heat -induced birefraction utilize the Nd:YAG self- aperture effect more than 50 W average power 1.064 um IR output is obtained with beam quality factor (M2) equals 3.19. Through the LD-Pumped Nd:YAG laser cutter we developed with short focus length negative spherical aberration focusing lens double axis linear step motor positioning system suitable beam expander multiplying factor appropriate diameter of exit beam aperture proper repetition rate when the cutting velocity equals 400mm/min 0.75mm thick silicon wafer can be penetrated
	Research on LD-Pumped dual wavelength Nd:YAG Laser with high beam quality for machining (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Zhang G.; Zhang G. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 Considering laser medium thermal lens effect and thermal focal length changes with pumping power conventionally lasers are designed to operate in the middle of thermal stable zones where the fundamental mode size is insensitive to thermal perturbation while this method seems impossible when large fundamental mode size is required. Through self-select mode cavity lasers are designed to work at the border of stable zone instead where large fundamental mode size in gain media can be reached. With increase of pumping power and self-aperture mode-selective effect mode size would grow up automatically to a certain value suitable for monomode resonance. With double 180 W pump modules acoustic Q-switch and LBO external frequency-doubled over 28 W which M2 equals 4.5 quasi-CW output green laser and 52W 1.064 um IR output is obtained simultaneity. With the insertion or not of the harmonic separator by footswitch high beam quality green IR and green IR lasers are obtained conveniently.