为了探测地球大气中的温室气体含 量，设计了4种空间分辨率为2 km、地面刈幅宽度为500 km、轨道高 度为690 km的气体探测仪光学系统。4个波段的中心波长分别 为1.606 m (弱CO2)、1.660 m (CH4)、 2.064 m (强CO2)和0.765 m (O2)； 光谱分辨率分别为0.08 nm/20000、0.08 nm/20000、 0.1032 nm/20000和0.045 nm/17000。 整个光学系统由浸没式平面衍射光栅、利特 罗式光学结构以及前置系统构成。该系统在奈奎斯特频 率处的调制传递函数(Modulation Transfer Function, MTF)值 接近80%，且单个像元尺寸内集中了接近90%的衍 射能量，可以实现高光谱探测。

To detect the concentration of greenhouse gas in the atmosphere of the earth, four kinds of gas detection optical systems with the spatial resolution of 2 km, the ground swath of 500 km and the orbit altitude of 690 km are designed. The central wavelengths of the four wavebands are 1.606 m (weak CO2), 1.660 m (CH4), 2.064 m (strong CO2) and 0.765 m (O2) respectively. Their spectral resolutions are 0.08 nm/20000, 0.08 nm/20000, 0.1032 nm/20000 and 0.045 nm/17000 respectively. The whole system consists of an immersed plane diffraction grating, a Littrow optical structure and a front optical system. Its Modulation Transfer Function (MTF) at the Nyquist frequency is close to 80% and the diffraction energy in a single pixel size is close to 90%. So, the system can be used to implement hyper spectral detection.