月基望远镜杂散光PST研究与测试

针对月基望远镜（LOT）杂散光抑制能力的验证，在地面采用点源透过率法对其遮光罩视场外杂散光抑制比进行了测试，并利用光学系统视场外不同离轴角的点源透过率（PST）来评价其杂散光抑制比。该PST测试方法突破了以往的杂散光测试方法，采用高精度星模拟器与EMCCD结合的思路，保证了探测器在其线性区域内具有大动态范围探测能力的特性，其动态探测范围可达1012，可满足指标PST（在22离轴角）测试值10-7的要求。该方法能更客观、更直接地反应遮光罩的杂散光抑制能力，其PST（在22离轴角）测试不确定度可优于60%，远远高于以往杂散光抑制比的测试精度。另外，讨论了该测试方法需改进的几点措施，PST测试预期目标可达10-12。最后通过试验对LOT相机遮光罩的杂散光抑制比进行测试，验证了LOT相机杂散光抑制比满足设计要求。

PST research and measurement of lunar-based optical telescope stray light

To verify suppression capability of the stray light of the lunar-based optical telescope (LOT), its stray light rejection ratio of glare shield out of field range by point source transmittance on ground was tested, and assessing its stray light rejection ratio with PST of optical system diversity angle of offaxis. The new test method of PST breaks through the tradition method of stray light, using a new method that is combining high degree of accuracy star simulator with EMCCD, guaranteeing that the detector has large dynamic region within its linear range, and the dynamic range is 1012. It could satisfy the indexing demand that the PST testing result is 10-7 (at 22angle of off-axis). This test method could objectively and directly reflect the stray light rejection ratio of glare shield. The testing uncertainty of PST is above 60%, it will exceed the testing precision of classical stray light testing method. Moreover, discussing the improving method,the target PST testing result will reach 10-12. Last it verify the PST of LOT catering design demand with the experiment that it test stray light rejection ratio of glare shield.