空间望远镜的设计仿真和低温波前测试

打开文本图片集

中图分类号：TH74 文献标识码：Adoi：10. 37188/OPE. 20253306. 0895

CSTR：32169. 14. OPE. 20253306. 0895

Performance simulation and wavefront measurement of telescope at cryogenic temperature

SONG Junru*，TONG Weiming，JIN Zhongrui，HE Dongke，LIU Zhiyuan，MA Yue （Beijing Institute of Space Mechanics & Electricity，Beijing ，China） * Corresponding author， E -mail：sjr1987bit@163. com

Abstract：Cryogenic space telescope is applied in 90K cryogenic environment，but developed in a laborato⁃ ry environment at room temperature and pressure. The huge differences in application and development en⁃ vironments result in two different sets of parameters of optical components. A telescope with good image quality at cryogenic temperature is actually a system with large aberration in laboratory environment. In or⁃ der to quantitatively evaluate the imaging quality of a cryogenic telescope，a structural thermos optical per⁃ formance simulation was conducted，and a testing method for wavefront error of the telescope in a 90K cryogenic environment was designed. Firstly， the working temperature of the telescope at 90K is achieved through the dual cooling of liquid nitrogen cold shroud radiation and refrigeration machine in the vacuum chamber. The wavefront measurement of the telescope is achieved through the interference mea⁃ surement of parallel light tube beam expansion. Secondly，the error sources of the testing system were ana⁃ lyzed and calibrated to correct the test results. Finally，the consistency between the measured cryogenic wavefront values and the model simulation of the telescope was compared and analyzed，as well as the manifestation of wavefront errors and the corresponding mapping relationship of structural design. The ex⁃ perimental results show that the design simulation of the telescope is accurate，the 90K low-temperature wavefront testing method is reasonable and feasible，the simulation accuracy is better than 20nm ，and the wavefront testing accuracy is better than 9nm . The test results can be used for the design improvement of the optical mechanical system of the space telescope.

Key words：telescope；design simulation；wavefront at cryogenic；interferometric measurement

1 引 言

空间技术的发展对探测仪器分辨率的要求越来越高。（剩余12261字）