一种光机一体化平面反射镜结构设计及应用分析

Structure design and application analysis of an opto-mechanical integrated plane mirror

为满足空间光学系统高成像质量、高稳定性和高杂散光抑制效果的需求,文章从选材、选型及仿真设计等方面开展研究,提出了一种新型光机一体化反射镜无框结构优化方案。方案的光学镜面通过钛合金表面烧结玻璃技术实现16∶1的镜坯光学面本体径厚比,加工难度与成本显著低于碳化硅与铍反射镜。经静应力与模态分析:反射镜结构稳定,重力及安装应力对镜面面形的影响可忽略不计,样件实测面形误差峰谷值<0.65λ,均方根值<0.12λ(λ=632.8nm),通过了相关环境性试验验证;经系统建模及杂散光分析:敏感角度斜入射视场光通量透过率可降低至传统光机分离设计的5~20%左右。设计方案已经成功在轨应用,为星载光学成像高光学稳定性与高杂散光抑制需求的实现提供了一种可借鉴的技术手段。

In order to satisfy the need of high imaging quality,stability and rejection of stray light in aerospace optical systems,a scheme of optimized borderless mirror structured based on Opto-Mechanical Integrated Technology is drafted in this journal article.The optical surface of the scheme is realized by the technology of surface-sintered glass on titanium alloy to achieve the diameter-to-thickness ratio of 16∶1of the body of optical surface of the blank of the mirror.The difficulty and cost of machining is significantly lower than silicon carbide and beryllium mirrors.According to the result of analysis of static force and frequency,it can be concluded that the mirror is structurally stable,the influence of gravity and assembly stress is neglectable.The measured values of error of the optical surface of the sample are:Peak-to-valley value<0.65λ.Root mean square value<0.12λ(λ=632.8nm).The stability was verified in the environmental test.According to the result of analysis of stray light,the illuminance transmittance on sensitive angles will descend to around 5%to 20%of the traditional Opto-Mechanical separated design.The design has been successfully applied in orbit,and the scheme provides technical access of realizing the need of high optical stability and rejection of stray light on aerospace imaging devices that can be references.