星载高光谱成像仪光学系统的选择与设计

本文概述了目前高光谱成像仪所采用的光学系统结构，分析讨论了棱镜色散、光栅色散、傅立叶变换三种主流高光谱成像仪分光方式的结构原理和优缺点，棱镜色散光能利用率高，但体积大，棱镜材料受空间环境变化影响较大，光栅色散效率低，但体积小，受环境影响小，傅立叶变换光谱成像系统由于分光棱镜的存在，能量至少损失50%以上。文中对国内外高光谱成像仪采用较多的Offner凸光栅光谱成像系统进行了论述，根据应用目标设计了一个离轴三反射镜望远系统和变倍Offner凸光栅组合的高光谱成像仪光学系统，该系统具有体积小、成像质量好、无光谱畸变的优点，通过加大光学系统的相对孔径，增加系统的入射光能量，弥补了光栅衍射效率低的缺点。

Selection and design of optical systems for spaceborne hyperspectral imagers

The paper outlines the optical systems applied in present hyperspectral imagers. The principle and characteristics of three spectrum-dividing methods with prism, grating and FT(Fourier Transform) are discussed, prism dispersion spectrometer results in high utilization rate of input light energy, but large volume and unreliability limit its application in spaceborne hyperspectral imager, grating dispersion spectrometer has low diffraction efficiency, small volume and stability in space, FT spectrometer only has no more than 50% efficiency due to beam splitter. The paper gives some representative optics adopted by present spaceborne hyperspectral imagers. Finally, an optical system with TMA telescope and two Offner convex grating spectrometer, used in a compact spaceborne hyperspactral imager is designed, small volume, high imaging quality and no spectral distortion make it applicable in spaceborne hyperspectral imager. Enlarging relative aperture of optical system can recuperate low diffraction efficiency.