重力对空间相机系统波像差影响的光机集成分析与验证

对空间离轴相机在重力载荷作用下的系统波像差变化进行了集成仿真分析,同时研究了分析结果的精度。介绍了集成仿真分析技术的基本流程和关键技术,对比分析了ZERNIKE多项式拟合法与形函数插值法两种面形畸变转换接口算法的优劣。介绍了常用的两种形函数构造方法的基本原理,基于面积法构造形函数得到了光学元件面形畸变的接口文件。最后,在相机的光机结构装调完毕后,对系统波像差在重力载荷作用下的变化进行了测试。测试结果表明,该空间相机3个视场系统波像差的变化量分别为0.029 8λ(-1视场)、0.019 4λ(0视场)、0.052 3λ(+1视场),与分析结果基本吻合。3个视场分析结果的误差分别为0.002 4λ(-1视场)、-0.000 9λ(0视场)、0.007λ(+1视场,)均小于0.01λ,满足工程设计的要求,验证了集成仿真分析结果的准确性。此外,通过集成分析技术定量得到了不同影响因素对系统波像差的影响,基于此优化设计光机结构,改善了重力对空间相机3个视场系统波像差的影响。

Integrated optomechanical analysis and experiments for influence of gravity on wavefront aberration of space camera

The variation of the wavefront aberrations of a Three-mirror Anastigmat(TMA) space camera under gravity was analyzed by integrated analysis method and the analytical accuracy was discussed. The basic process and key technology of the integrated analysis method were introduced, two kinds of surface distortion conversion interface algorithm (ZERNIKE polynomial fitting method and shape function interpolation method) were compared. Then, the principles of two kinds of shape functions were introduced, and the interface file of the optical element surface distortion was obtained by the area coordinate method. Finally, the variations of wavefront aberrations in gravity load were tested after the camera alignment was completed. Test results show that the variations of the wavefront aberrations of the three fields of view are respectively: 0.029 8λ(-1), 0.019 4λ(0), and 0.052 3λ(+1), which are agreement with that of the analysis results. The errors of the analysis results of the three fields of view are respectively 0.002 4λ(-1), -0.000 9λ(0), 0.007λ(+1), all less than 0.01λ, meet the requirements of engineering and verify the correction of the integrated analysis method. Meanwhile, the quantitative effects of each factor on the system wavefront aberrations were obtained by the integrated analysis method. On the basis of the optimization design with the integrated analysis method, the influences of gravity on wavefront aberrations of the three fields of view of the space camera is significantly improved.