大口径非球面主反射镜的装调方法研究

Alignment method for large aperture aspheric mirror

针对大口径非球面主反射镜(简称主镜)的装调要求,对比分析常用大口径非球面面形检测方法,提出该类主镜检测面形的最佳方案。在主镜的装调过程中,通过对主镜的固定方式和主镜变形补偿这2个关键环节的阐述,总结主镜固定的难点及主镜变形的原因,提出一套全新的装调方案,以旋转消重力法进行检测,并用专用工装实时定心调节,再用辅料焊接法固定主镜与中心轴,最后采用辅助支撑对主镜组件进行最终固定修正。装调结果表明:对于大口径非球面反射镜,装调完成后的主镜面形精度Rms≤0.03λ(λ=632.8nm)。

According to the alignment demand of the large aperture aspheric mirror（hereinafter to be referred as the main mirror）,the common detection methods for the large aperture aspheric surface were comparatively analyzed,and the best method for this sort of surface shape detection was put forward.In the alignment procedure of the main mirror,the two key links of the main mirror＇s fixation and deformation compensation were expounded,the difficulties of the fixation and the reasons for the deformation were summarized,and then a fire-new set of project was established by using measurement method with circumrotation counteracting gravity,real-time center position controling with particular tools,assistant material jointing method for the main mirror fixation and finally adjusting fixation with assistant upholders.The result showed that the method obtained good experimental effect,and the surface shape error of the main mirror was less than or equal to 0.03λ（λ=632.8nm）.