高通量傅里叶变换成像光谱仪调制度分析

介绍了高通量傅里变换成像光谱仪的概念，分析了其中使用的改进型Mach-Zehnder干涉仪的原理,计算出其光程差以及调制度.可以看出:要得到较好的调制图形，必须满足两像面夹角和像方孔径角都是小角的条件，且两个像点之间的横向距离和纵向距离越小越好.讨论了像面与探测器平面之间的横向和纵向偏差及CCD单元尺寸等因素对光谱仪调制度的影响.通过调节各参量，三种调制度都可以达到90％以上，能够满足光谱仪应用需求.

The Analysis of the High (E)tendue Imaging Fourier Transform Spectrometer

The conception of the High Etendue Imaging Fourier Transform Spectrometer (HEIFTS) is introduced and the principle of the modified Mach-Zehnder interferometer,which is used in the spectrometer,is analyzed. Meanwhile,the optical path difference and the degree of modulation of this kind of interferometer are calculated. It's easy to be found that,in order to get the better diagram of the degree of modulation,both the inclination of the two image planes and the image aperture angle must be small angles,and both the lateral and longitudinal offsets must be smaller. Then the effects on the degree of modulation by the offsets and the dimension of the CCD array are discussed. By adjusting the parameters,the three degrees of the modulation can reach 90%,which can satisfy the application requirement of the spectrometer.