凸面光栅成像光谱仪的干涉法装调

摘要

How to align the spectral systems of Offner concentric imaging spectrometers with convex gratings was researched. Based on the principle of dual-beam interference and characteristics of concentric systems,an interferometric alignment method for the Offner imaging spectrometers with convex gratings was proposed. With this method , the primary and tertiary mirrors of Offner imaging spectrometers were aligned firstly. As the defocus of single spherical mirror could not be aligned to zero, the relative defocus was introduced to adjust the defocuses of the two mirrors to achieve the concentricity. Furthermore,because the concave compensator could not test the convex mirror,the convex grating was arranged according to reading spectrogram directly to complete concentric alignment with high precision. The result indicates that the interferometric alignment can achieve the distance between centers of the primary and tertiary mirrors of Offner imaging spectrometers up to several nano-meters or near zero.%研究了Offner凸面光栅成像光谱仪同心分光系统的装调方法.将双光束干涉基本原理与同心光学系统基本特点相结合,提出了适用于Offner凸面光栅成像光谱仪的干涉装调法.该方法首先对凸面光栅成像光谱仪同心光学系统的两个凹球面反射镜进行同心装调,由于单个球面反射镜的离焦量难以调整至零,故引入相对离焦使两个反射镜的离焦量相等,从而实现两镜同心.另外,考虑无法用同一套凹球面补偿镜来检测凸球面,故提出采用谱图直读法来确定凸面光栅位置,实现了Offner凸面光栅成像光谱仪的高精度同心装调.实验结果表明,经干涉法装调后,分光系统主镜和三镜的球心距离可以达到几个纳米甚至更高.