光谱仪动镜倾斜误差分析及其动态校正技术研究

Error analysis of the mirror tilting in spectrum transform interferometer and the study on dynamic alignment technology

采用了双光束干涉的迈克尔逊干涉仪系统的傅里叶变换红外光谱仪,在动镜运动过程中,动镜可能在三个方向发生倾斜。通过建立干涉面光强分布的二维数学模型,确立了干涉图函数的数学表达式,从调制度、相位误差和频率噪声的角度,对动镜倾斜误差进行了系统分析。在误差分析的基础上,对动镜容许的最大倾斜角度进行了讨论,并对其动态校正技术的要点做了分析。

The Michelson interferometer system which has two-beam interference is applied in Fourier Transform interferometer, the moving mirror could tilt in three directions in motion. In this paper, a two dimension mathematical model of the interferential plane is brought out, and the function of the interferogram is established. By analyzing the modulation depth, phase error and frequency noise, the error of the moving mirror is studied theoretically. Based on the error analysis, the max titling angle can be computed, the key methods on dynamic alignment are also discussed.