高分辨力凹面光栅光谱仪的优化设计

摘要

本文从凹面光栅的理论分辨力和像差、狭缝的宽度和高度、光栅基片的尺寸大小等角度出发，推导了系统分辨力的计算公式，得出系统优化设计的新方法。得出以下结论：系统不能通过无限增加光栅刻线数来提高分辨力；狭缝宽度的选择要综合考虑入射光的能量和分辨力的大小；狭缝宽度对系统分辨力的影响远远大于狭缝高度和凹面光栅的理论分辨力的影响；提出了基片尺寸大小的计算公式和优化设计的方法。本文的理论计算值与实验结果相一致。%Taking into account the theoretical resolution of the concave gratings, the aberration, the width and height of the slit and the size of the grating, mathematical expression for the resolution of the system was deduced and a new method for simulating and testing the system was proposed. We drew some following conclusions. The system can not improve the resolution by increasing indefinitely grating lines. The energy and the resolution are considered to select an appropriate width of the slit. The impact of the width of the slit on the system resolution is far greater than that of the height of the slit and the theoretical resolution of the concave grating. And then, a formula of the size of the gratings and a method for optimizing were proposed. The theoretical calculation values coincide with the experimental results.