一种基于调节三镜的空间光学相机离焦补偿方法

离焦补偿是空间光学相机获得良好成像品质的关键。文章基于空间光学相机的技术特点分析其离焦补偿方法，提出调节三镜的离焦补偿方法。利用CODE V光学软件对某高性能光学小相机的光学系统进行仿真分析，获得离焦补偿精度、离焦补偿范围与系统成像品质的关系。为保证光学系统对移动三镜倾角控制要求，对三镜调焦机构直线精度及其力学稳定性进行了测试，最后对相机进行了地面外景成像验证与在轨测试。仿真及试验测试结果表明，调节三镜能有效地补偿空间三反相机在轨各因素引起的系统离焦，满足相机在轨成像品质要求。

A Method of Defocus Compensation for Space Optical Camera by Adjusting Tertiary Mirror

Defocus compensation is the key to obtain high quality image for the space optical camera. The mechanism of defocus compensation is investigated based on the technical characteristics of space optical camera. A way to compensate the defocus through adjusting the tertiary mirror is proposed. Optical system of a high-performance optical camera is simulated by optical software CODE V. The correlation between image quality of the system and defocus compensation precision, defocus compensation range and other parameters are obtained. In order to ensure angle control requirements when mobiling the tertiary mirror for the optical system, linear precision and its mechanical stability are tested for the tertiary mirror focusing mechanism. At last,Both ground scenery imaging and orbit test are carried out for the camera. Simulation analysis and ex-perimental results demonstrate that for a coaxial three-mirror camera on orbit, adjusting its tertiary mirror can compensate system defocus caused by orbital factors, which meets the requirement of imaging quality for the camera on orbit.