作为一个微弱光信号探测系统, 拉曼光谱仪中的杂散光分析可以为其设计提供较大帮助。 针对微型拉曼光谱仪系统, 结合光学设计和三维建模优化了其光机结构, 系统分辨率为0.7 nm, 体积为110 mm×95 mm, 属便携式微型拉曼光谱仪, 并基于杂散光分析软件TracePro对系统进行了光线追迹和仿真分析。 首先通过优化孔径光阑初步抑制了入射处带来的杂散光, 然后针对系统内部的主要杂散光（光栅零级衍射光）抑制装置即光学陷阱进行了详细分析和设计改进, 改进后的光学陷阱较改进前更有效地利用了光谱仪内部空间, 且分析结果表明改进后的光学陷阱将杂散光线数量减少了50%, 杂散光归一化辐照度强度从10-5降低至10-7, 在微型化的同时可有效抑制微型拉曼光谱仪系统中的杂散光, 将更加有利于微弱信号的探测, 为微型拉曼光谱仪的设计和装调提供了参考。

Stray light analysis has great benefits in designing Raman spectrometry system, which is the sensitive detection system of weak optical signal. In this paper, optical design software and Solidworks are utilized to optimize the optical and mechanical structure. The system resolution is 0.7 nm, and the volume is 110 mm×95 mm, which belongs to portable and miniature Raman spectrometer. Based on the stray light simulation model, we made an analysis of ray tracing simulation for this system. First, the stray light come with the incident ray were suppressed by the aperture stop. Then the receiver of stray light was introduced and improved in the design progress to suppress internal stray light, especially for zero-order diffraction light of plane grating. The improved receiver of stray light is more effectively using the internal space of the spectrometer and analysis results show that a 50% reduction in the number of stray light and stray light normalized irradiance intensity from 10-5 down to 10-7. The analysis shows that the improved receiver of stray light can effectively suppress stray light, which is beneficial to weak signal detection, and provide reference for design and adjustment of the miniature Raman spectrometer.