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	DIN18CrNi18合金钢毫秒激光打孔孔型研究学位论文 OAI收割北京: 中国科学院大学, 2017 作者: SAAD NAWAZ \| 收藏 \| 浏览/下载：57/0 \| 提交时间：2019/05/15 激光打 ,离焦量锥角纵剖面重铸层 Laser drilling defocusing length Tapper angle longitudinal profile recast layer
	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：43/0 \| 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).
	Inspection focus technology of space tridimensional mapping camera based on astigmatic method (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China 作者: Wang Z.; Wang Z.; Zhang L.; Zhang L. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 The CCD plane of the space tridimensional mapping camera will be deviated from the focal plane(including the CCD plane deviated due to camera focal length changed) under the condition of space environment and vibration impact when satellite is launching image resolution ratio will be descended because defocusing. For tridimensional mapping camera principal point position and focal length variation of the camera affect positioning accuracy of ground target conventional solution is under the condition of vacuum and focusing range calibrate the position of CCD plane with code of photoelectric encoder when the camera defocusing in orbit the magnitude and direction of defocusing amount are obtained by photoelectric encoder then the focusing mechanism driven by step motor to compensate defocusing amount of the CCD plane. For tridimensional mapping camera under the condition of space environment and vibration impact when satellite is launching if the camera focal length changes above focusing method has been meaningless. Thus the measuring and focusing method was put forward based on astigmation a quadrant detector was adopted to measure the astigmation caused by the deviation of the CCD plane refer to calibrated relation between the CCD plane poison and the asrigmation the deviation vector of the CCD plane can be obtained. This method includes all factors caused deviation of the CCD plane experimental results show that the focusing resolution of mapping camera focusing mechanism based on astigmatic method can reach 0.25 m. 2010 Copyright SPIE - The International Society for Optical Engineering.