红外高通量干涉成像光谱仪的设计与验证

Design and validation of infrared interferential imaging spectrometer with high flux

介绍了静态高通量干涉成像光谱技术的原理，针对红外波段目标辐射能低、系统易受自身辐射影响等特点，提出了基于分体式Sagnac干涉仪的红外高通量干涉成像光谱仪方案。分析了Sagnac干涉仪的设计方法，特别是分光镜对光线的偏折作用引起的横向剪切量和光线的折射光程不同带来的附加光程差。根据采样定理，计算了成像光谱系统对探测器和后置成像系统的要求。使用长波热像仪（光谱范围7．7～9．3μm）搭建了实验装置，实验结果表明，这种成像光谱系统能够准确测量出样品的光谱．验证了该方案的原理和设计。

Principles of static high-flux interferential imaging spectroscopy were introduced. On account of the features of low radiation of targets and sensitiveness to the radiation of the system itself in the infrared band, a program of infrared interferential imaging spectrometer based on the split-type Sagnac interferometer was proposed. Means of designing Sagnac interferometer was also analyzed, with the key points on the lateral shearing caused by the deflection of rays in the beamsplitter and the additional optical path difference brought by different refractions. On the basis of the sampling theorem, requirements for the detector and rear-optics of the imaging spectroscopy system were calculated. An experiment setup was built with a long-wave infrared camera working within 7.7-9.3 μm. Experimental results show that this imaging spectroscopy can accurately retrieve the spectrums of samples, validating the principles and design of this program.