用于空间目标偏振探测的望远镜系统偏振分析

Polarization Analysis of the Telescope System Used for Space Target Polarization Detection

基于地基大口径自适应望远镜构建成像偏振探测系统,可以同时获取空间目标的光强和偏振图像,将光强信息和偏振信息相结合,能为空间目标的探测和识别提供更多依据。现有的1.23m自适应望远镜在设计时并未采用保偏设计,在开展观测研究前需得到光学系统的偏振传输特性。但目前难以直接对大口径望远镜进行偏振标定,为了分析1.23m自适应望远镜光学系统的偏振传输特性,基于相干矩阵和光线追迹法建立了望远镜系统偏振传输特性分析模型。仿真得出了1.23m自适应望远镜光学系统的偏振传输特性,发现光学系统会引入较大的偏振探测偏差。为减小偏振探测偏差,给出了一个可行的保偏改进方案,并通过已建立的模型验证了该方案的有效性。

The polarization imaging system based on large aperture ground-based adaptive telescope can acquire both intensity image and polarization image at the same time. Richer information for detecting and identifying space target can be provided by the combination of intensity and polarization. Because the polarization-maintaining design of the 1.23 m ground-based adaptive telescope is ignored, the telescopePs polarization properties on propagation should be known before experiments. But it is difficult to calibrate the polarization properties of large aperture telescope. To analyze the polarization properties of the 1. 23 m ground-based adaptive telescope, an analysis model based on coherent matrices and ray tracing formulas is constructed. By simulation, impact of the optical system on the accuracy of polarizing detection is found. An improved scheme to decrease the deviation of polarizing detection is given and its effectiveness is identified by the model constructed above.