中国激光, 2011, 38 (4): 0409003, 网络出版: 2011-03-30
宽波段全息罗兰光栅的优化
Optimization of Rowland Circle Mounts for Broad-Band Spectrographs
摘要
罗兰光栅存在的主要像差是像散和弧矢彗差,影响其光通量和光谱分辨率。根据凹面全息光栅的几何像差理论,分析了记录光源点在罗兰圆外所制作的全息罗兰光栅的宽波段像差特性。发现像散和弧矢彗差能够在两个波长处被同时消除;并且在两波长之间的波段范围内,像散和弧矢彗差相对传统光栅均得到明显改善。基于此像差特性提出一种设计宽波段高分辨罗兰光栅的方法,通过选择适当的使用结构和校正波长,能够在整个使用波段有效地校正像散和弧矢彗差。利用这种优化方法设计了工作波段为160~600 nm的罗兰光栅。光线追迹结果显示,所设计光栅的光谱分辨率和能量集中度在整个使用波段较传统光栅均有显著提高。
Abstract
The main residual aberrations of Rowland circle mounts are astigmatism and sagittal coma, which seriously deteriorates the throughput and spectral resolution. An analytic study on the aberration property of a Rowland circle mount which is recorded with the off-Rowland recording geometry is presented. It is found that the astigmatism and sagittal coma can be simultaneously eliminated for two wavelengths, between which the aberrations are both greatly reduced. The Rowland-circle mounts used for broad-band spectrographs can be optimized by properly choosing the using geometry and correction wavelength. A grating working in the wavelength range of 160~600 nm is designed and compared with a conventional grating. The result indicates that significant reduction of the astigmatism and improvement of resolution are both achieved over a wide wavelength range.
孔鹏, 巴音贺希格, 李文昊, 唐玉国, 崔锦江. 宽波段全息罗兰光栅的优化[J]. 中国激光, 2011, 38(4): 0409003. Kong Peng, Bayanheshig, Li Wenhao, Tang Yuguo, Cui Jinjiang. Optimization of Rowland Circle Mounts for Broad-Band Spectrographs[J]. Chinese Journal of Lasers, 2011, 38(4): 0409003.