讨论一种新型干涉选择调幅光谱仪的光路设计.利用补偿板的扭动实现振幅调制，文章同时对幅射通量和分辨率进行了理论分析，采用矩形光栏时，分辨率为光栅分辨率的1.35倍.文章还讨论了采用椭圆形光栏时，仪器函数曲线的切趾.

A new type of interference selective amplitude modulation spectrometer is discribed in this paper. The diffraction grating illuminated by a collimated incident beam is placed in front of a Twyman interferometer. The beam is splitted into two parts and reflected by two mirrors acting as two diffraction gratings. Then the interference fringe is modulated. The theoretical analysis of flux and resolution is made. Using rectangle diaphragm the resolution of 1. 35 times of the grating is obtained. The apodization technique with elliptical diaphragm is discussed.