空间调制傅里叶变换红外光谱仪多级微反射镜倾斜误差分析

空间调制傅里叶变换红外光谱仪无可动部件，系统稳定而紧凑，而且程差可控，可实现在线监测和实时检测。多级微反射镜是光谱仪干涉系统的关键器件，其在系统中的位置精度对光谱仪性能影响很大。本文对多级微反射镜的倾斜误差引起的光程差变化进行了理论计算，并利用光学软件进行了模拟仿真。分析结果表明，随着多级微反射镜倾斜角度的增大，干涉图对比度下降，对应的光谱图脉冲谱线展宽，信噪比下降，严重时会出现波数偏离。以上分析方法对后期系统公差分配及装调有着重要的指导意义。

Analysis of Multi-Micromirrors Tilt Error in Space-Modulated Fourier Transform Infrared Spectrometry

The system of space-modulated Fourier transform infrared spectrometer without moving parts is stable and compact, moreover, it can realize the on-line monitoring and real-time detection. The position accuracy of multi-micromirrors as the key components has a great influence on spectrometric performance. In the present paper, the multi-mcromirrors tilt error caused by optical path difference changes was calculated and simulated. The analysis shows that, as the multi-micromirrors tilt angle increased, the interference pattern contrast decreased and the signal to noise ratio reduced. The results could be used in the tolerance distribution and the systemic alignment in the next step.