Guo Xiaohu, Dong Liquan, Zhao Yuejin, Jia Wei, Kong Lingqin, Wu Yijian, Li Bing
Appl Opt. 2015 Apr 1;54(10):2798-805. doi: 10.1364/AO.54.002798.
Wavefront coding (WFC) technology is adopted in the space optical system to resolve the problem of defocus caused by temperature difference or vibration of satellite motion. According to the theory of WFC, we calculate and optimize the phase mask parameter of the cubic phase mask plate, which is used in an on-axis three-mirror Cassegrain (TMC) telescope system. The simulation analysis and the experimental results indicate that the defocused modulation transfer function curves and the corresponding blurred images have a perfect consistency in the range of 10 times the depth of focus (DOF) of the original TMC system. After digital image processing by a Wiener filter, the spatial resolution of the restored images is up to 57.14 line pairs/mm. The results demonstrate that the WFC technology in the TMC system has superior performance in extending the DOF and less sensitivity to defocus, which has great value in resolving the problem of defocus in the space optical system.
空间光学系统采用波前编码（WFC）技术来解决因温差或卫星运动振动引起的离焦问题。根据WFC理论，我们计算并优化了用于同轴三镜卡塞格伦（TMC）望远镜系统的立方相位掩膜板的相位掩膜参数。仿真分析和实验结果表明，在原始TMC系统焦深（DOF）的10倍范围内，离焦调制传递函数曲线和相应的模糊图像具有完美的一致性。经过维纳滤波器的数字图像处理后，恢复图像的空间分辨率高达57.14线对/毫米。结果表明，TMC系统中的WFC技术在扩展DOF方面具有优异性能，并且对离焦不太敏感，这在解决空间光学系统中的离焦问题方面具有很大价值。
