准直系统对静态傅里叶变换光谱仪的影响

摘要

准直系统为静态傅里叶变换光谱仪提供准直光，其品质对光谱仪复原光谱的信噪比有着决定性的影响。研究基于菲涅尔标量衍射理论，通过数值计算软件建立了静态傅里叶变换光谱仪的物理光学仿真模型，详细探讨了准直镜头各种赛德尔像差及扩展光源尺寸对静态傅里叶变换光谱仪的影响。仿真结果表明：各类像差对光谱信噪比影响的大小呈现明显的规律性；特别是，轴外像差对光谱信噪比的影响还与光源点所处的象限位置有关；最后仿真得到了扩展光源的最大容许半径为0.65 m m。此研究结果将用于准直系统的设计。%Collimation system provides collimated light for the static Fourier-transform spectroscopy (SFTS) .Its quality is cruci-al to the signal to noise ratio (SNR) of SFTS .In the present paper ,the physical model of SFTS was established based on the Fresnel diffraction theory by means of numerical software .The influence of collimation system on the SFTS was discussed in de-tail focusing on the aberrations of collimation lens and the quality of extended source .The results of simulation show that the in-fluences of different kinds of aberrations on SNR take on obvious regularity ,and in particular ,the influences of off-axis aberra-tions on SNR are closely related to the location of off-axis point source .Finally the extended source's maximum radius allowed was obtained by simulation ,which equals to 0.65 mm .The discussion results will be used for the design of collimation system .