基于Wollaston棱镜的图像复分快照式成像光谱仪设计

设计一种以Wollaston棱镜为分光元件的图像复分快照式成像光谱系统，主要包括前置望远物镜、准直镜、Wollaston棱镜组、成像镜和补偿滤光片。此类光学系统可以一次曝光获取同一目标景物在不同波长下的二维信息。光束经过Wollaston棱镜组分光，为了使不同波长对应景物不至于重叠，要求分束角度比较大，这样进入成像镜的光线入射角度相对较大，无疑增加了成像镜的设计难度。分析了基于Wollaston棱镜的图像复分快照式成像光谱仪的原理及特点，设计了一套完整的成像光谱系统。全系统结构复杂，光学系统的光阑必须匹配好。为了使得不仅单个镜头成像质量良好，而且镜组之间能够良好的衔接，将前置望远物镜设计为像方远心结构，准直镜设计为物方远心结构。全系统采用多重结构，使得16个谱段在56线对处的MTF值均接近衍射极限，点列图中RMS值基本都在艾里斑以内，系统成像质量良好。

The Snapshot Imaging Spectrometer with Image Replication Based on Wallaston Prism

In this paper,a kind of snapshot imaging spectrometer is designed by using image replication based on Wollaston prism.The system includes telephoto lens,collimator lens,Wollaston prism,the imaging lens and compensation filters.With this optical system,we can obtain two-dimensional information at different wavelengths of the same target through one time ex-posure.When Light beam is passing Wollaston prisms,in order to make sure that the different wavelengths will not overlap,the Wollaston prism needs to be designed with relatively large beam splitting angle.Then the incidence angle of the imaging lens is relatively large.It will increase the difficulty of the imaging lens design.We design,analyze the principle and the characteristics of the snapshot imaging spectrometer using image replication based on Wollaston prism,and design a complete set of imaging spectrometer system.The structure is complex;the aperture of the optical system must be well matched.In order to make sure that we can obtain good image quality through the single lens,but also the whole system,we design the telephoto lens which is imaging telecentric structure,the collimator lens which is obj ective telecentric structure.We use the multiple structures in ZEM-AX to optimize the 1 6 spectral bands.At 5 6 lp·mm-1 ,the MTF is close to the diffraction limit,the RMS of the SPT is in the Airy disk,proving good image quality.