空间遥感相机中心支撑主镜的优化设计

Optimum design on the primary mirror central supported in a space remote sensing camera

为了设计并加工轻重量、高刚度的用于Ｃａｓｓｅｇｒａｉｎ式空间遥感相机中的主镜，首先根据重量和自然频率的高低优选主镜的背部基体形状。利用有限元法对自重作用下主镜的面型变化进行了分析计算，并对主镜的面型变化进行了Ｚｅｒｎｉｋｅ多项式数据处理，实验证明分析计算的结果正确合理，同时说明加工工况与相机使用时的装配状态一致的重要性。最后对主镜的背部轮廓形状进行了优化。

A central supported primary mirror of Cassegrain system used in space remote sensing camera is studied in this paper. In order to obtain a lightweight and high stiffness mirror, the best rear shape is selected by the criteria of weight and natural frequency. By means of Finite Element Method (FEM), calculation and analysis of deformation for the surface figure, under the gravity, is carried out. The computed data is fitted at terms of Zernike Polynomials. The experiment result meets the computed data, which proves that the calculation is correct, and dit is strongly suggested that the machining status of the primary mirror is as the same as its assembly status. At last, the back profile of the primary mirror is optimized.