光学 精密工程, 2015, 23 (4): 1027, 网络出版: 2015-05-20
小型光学遥感器主镜室的光机结构
Support structure of primary mirror for small optical remote sensor
遥感器 主镜 挠性支撑 模态分析 冷加工 电火花加工 remote sensor primary mirror flexure support modal analysis cold machining electrical discharge machining
摘要
设计了一种新的光机结构,以使超小型光学遥感器在宽温度范围及恶劣的动力学环境下能够良好成像。研究了该结构中的核心部件-主镜组件的支撑结构的设计原理和实现方法。通过对主镜室初始设计方案的力、热特性分析, 说明了主镜传统支撑方式的局限性。然后,以挠性支撑原理为基础设计了一种新型的适用于小口径反射镜支撑的挠性反射镜支撑结构,对该支撑结构的温度适应性及组件的模态进行了有限元分析,说明了采用这种反射镜挠性支撑结构能够满足设计指标要求。最后,论证了小型光学遥感器主镜室的加工及具体实现方法。对装配后的主镜组件进行了热冲击试验和温度拉偏试验,结果表明: 在-60 ℃~80 ℃进行热冲击试验后,主镜不会出现炸裂现象; 而在-20 ℃~50 ℃温度下,反射镜面形精度RMS仍保持在 0.025λ(λ=632.8 nm)水平。 得到的结果验证了主镜室的设计可以满足小型光学遥感器的应用环境要求。
Abstract
An opto-mechanical structure for a microminiature optical remote sensor was designed to obtain favorable images under a wider temperature range and severe dynamic environments. The design principle and concrete realization method of the support structure of a primary mirror and the most critical core component in the whole opto-mechanical structure of the optical remote sensor was researched. The boundedness of traditional supporting way of a primary mirror was explored through analysis on the mechanical and thermal properties of primary mirror chamber in the initial designing scheme. Then, a new-style and flexure support structure suitable for a mini-style mirror was designed based on flexible support principle. The thermal adaptability and dynamics environment suitability of the support structure were analyzed by finite element method, which verifies that the flexible support structure could meet the design requirements. In the end, the processing and concrete implementing methods of the primary mirror chamber of the optical remote sensor were presented. The experiments of thermal shock test and partial test on the primary mirror were performed. The results show after thermal shock test, the primary mirror won't appear the crack phenomenon at -60 ℃ -80 ℃. Moreover, the surface figure accuracy RMS of the mirror remains a level of 0.025λ (λ=632.8 nm) in -20 ℃ to 50 ℃. These results demonstrate that the primary mirror design satisfies the application environment requirements of the optical remote sensor.
辛宏伟, 刘巨, 刘磊, 关英俊. 小型光学遥感器主镜室的光机结构[J]. 光学 精密工程, 2015, 23(4): 1027. XIN Hong-wei, LIU Ju, LIU Lei, GUAN Ying-jun. Support structure of primary mirror for small optical remote sensor[J]. Optics and Precision Engineering, 2015, 23(4): 1027.