基于多视场波前传感的次镜位置误差检测方法

大口径分块式主镜空间对地遥感系统在轨工作时，次镜相对于主镜的位置失调会对系统像质产生影响，需对其进行在轨检测与校正。当分块式主镜无中心基准镜时，无法用传统的灵敏度矩阵反演法计算出次镜失调量。为此，提出了一种基于多视场波前传感信息计算次镜位置失调量的方法，采用ZEMAX软件建立了无中心基准的36分块式主镜空间对地遥感系统。针对该系统像差特点，利用不同视场的场依赖波前像差，建立了次镜失调量检测数学模型，开展了仿真研究，结果表明当波前传感误差为1/40（=632.8 nm）时，次镜位置失调量的检测精度X、Y方向平移约为30 nm，倾斜约为15；失调量检测动态范围X、Y方向平移为0~1.5 mm，倾斜为0~0.03。并通过多组实际仿真，验证了所提方法的可行性。

Secondary mirror position error detection method based on multi-field wavefront sensing

When the space-to-ground optical remote sensing system with a segmented primary worked, the alignment degeneracies of secondary mirror relative to the primary mirror would have an impact on the image quality, which should be detected and corrected online. When there was no center segmented-mirror in the segmented primary mirror, the traditional sensitivity matrix inversion method would not be used to calculate the alignment degeneracies of secondary mirror. It proposed a method to calculate the misalignment of the secondary mirror by using the multi-field wavefront sensing information. Based on ZEMAX, it established a space-to-ground remote sensing system with 36 segmented primary mirror, in which there was no center mirror. For the optical system with special aberration characteristics, it built a mathematical model to obtain the misalignment of secondary mirror by means of the field-dependent wavefront aberration which can be got by multi-field wavefront sensing. The simulation results showed that when the wavefront sensing error is 1/40(=632.8 nm), the detection accuracy of the misalignment of secondary mirror on X,Y-translation and X,Y-tilt reached 30 nm and 15 respectively; the detection range of the misalignment of secondary mirror on X,Y-translation and X,Y-tilt are 0-1.5 mm and 0-0.03 respectively. And a lot of simulations based on the real space optical remote system were done to prove the feasibility of the proposed method.