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	Effect of gimbal point displacement on optical axis pointing precision in an image seeker (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 A concentric glass spherical dome was usually chosen as the transparent window mounted in front of the optical lens in an image seeker. However optical ray had to change its direction when propagating through the dome due to refraction unless passing through the center of the dome which demanded gimbal point coincide with the center of the dome exactly. In fact gimbal point displacement could not be eliminating due to fabrication assembly and vibration therefore the optical axis pointing error generated. In this paper the effect of gimbal point displacement on optical axis pointing precision in an image seeker was analyzed and the theoretical expression of the optical axis pointing error was derived based on geometric optics and the error dynamics was explored by numerical. Take a visible light image seeker as a case the thickness of concentric glass spherical dome was 8mm and the inner radius was 72mm and the optical axis pointing errors varying dynamically with the look angle and the gimbal point displacement were shown in graph. When the gimbal displacement was 0.11mm the maximum optical axis pointing error was 0.054mrad that is equal to the instantaneous field of view (IFOV) corresponding to the camera system whose focal length was 120mm and pixel size was 6.5m. Furthermore with the gimbal displacement increasing the optical axis pointing error increased linearly. The analyzed results provided a theoretical basis for the displacement range which had to be limited strictly in the gimbal design process. 2011 IEEE.
	Manufacture for ruling concave metal grating with a long focal length (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China Gao J.-X. 收藏 \| 浏览/下载：71/0 \| 提交时间：2013/03/25 The ruling technique for concave metal grating with long curvature radius (namely long focal length) is studied. In order to rule the concave grating with a long focal length the diamond carriage with elastic thimble mode is designed and manufactured. It is available not only to rule plane grating but to concave grating with a long focal length. The mathematic expression between the curvature radius of circular arc cutting edge of ruling tools for grating and the curvature radius of concave grating the caliber of grating and the size of transverse direction of bit tool are given. The span of curvature radius of circular arc cutting edge is analyzed theoretically. The concave metal grating with 30m curvature radius for 10.6m laser system is manufactured. The testing result shows that the quality of groove is perfect and the diffraction efficiency is more than 95.6 percent. 2010 IEEE.
	Investigation on micro-hardness with shear strain extent for copper specimens subjected to high pressure torsion 会议论文 OAI收割 International Conference on Experimental Mechanics 2008, ICEM 2008, Nanjing, China, November 8, 2008 - November 8, 2008 作者: Liu Y; Hong YS(洪友士); Fan KK; Ji XD 收藏 \| 浏览/下载：24/0 \| 提交时间：2017/07/14 Crystal particles Grain size Grain size refinement High pressure torsions Mechanical performance Metal materials Radius direction Saturation state Spatial distribution