星载多模式差分吸收高光谱成像仪是一种新型空间大气探测仪器，要求同时具有天底、临边和掩日等多模式探测功能，主要用于二氧化硫、二氧化氮等大气痕量气体探测。提出了利用两个扫描镜切换不同探测模式、利用双光谱仪减小系统的光谱杂光，利用分色片将工作波段分成3个通道实现多模式高光谱分辨率探测的新方法，设计了一个多模式差分吸收高光谱成像仪光学系统，瞬时视场为1.8°×0.04°，系统F数为2，工作波段为250~500 nm，分成250~310 nm、300~410 nm和400~500 nm 3个通道。利用ZEMAX-EE软件进行优化设计和分析，其中250~310 nm通道，光谱分辨率为0.12 nm，满足光谱分辨率不大于0.4 nm的指标要求；300~410 nm和400~500 nm通道，光谱分辨率分别为0.25 nm和0.23 nm，满足光谱分辨率不大于0.6 nm的指标要求。多模式差分吸收高光谱成像仪在空间维方向的调制传递函数（MTF）在特征频率0.25 lp/mm处达到0.98以上，能够满足空间多模式差分吸收高光谱大气探测的要求。

Space-based multi-model differential optical absorption hyperspectral imager is a new type space atmospheric sounder. It requires the multi-model sounding functions including nadir, limb and sun occultation. It chiefly sounds the trace gases such as SO2, NO2 and so on. A new method of multi-model sounding with high spectral resolution is proposed. The method uses two-scanning mirrors to switch differential sounding model, double-spectrometers to reduce the spectral stray light, and dichroic filter to divide working waveband into three channels. An optical system of multi-model differential optical absorption hyperspectral imager is designed. The instantaneous field of view is 1.8°×0.04°. The F number of the system is 2. The working waveband is 250~500 nm, which is divided into three channels, the first one is 250~310 nm, the second one is 300~410 nm, and the last one is 400~500 nm. Optimization design and analysis are performed by ZEMAX-EE software. The spectral resolution is 0.12 nm in the waveband of 250~310 nm, which satisfies the requirement specification of no more than 0.4 nm. The spectral resolutions are 0.25 nm and 0.23 nm in the waveband of 300~410 nm and 400~500 nm, respectively, which satisfy the specification requirement of no more than 0.6 nm. The modulation transfer function (MTF) of multi-model differential optical absorption hyperspectral imager is more than 0.98 at characteristic frequency of 0.25 lp/mm in the spatial dimension. The design results satisfy the requirements of multi-model differential optical absorption hyperspectral atmospheric sounding.