Optical design of multi-angle imaging spectropolarimeter

The atmospheric aerosol is one of the most important factors leading to the global climate change and air quality problems, it is very meaningful to detect the global atmospheric aerosol by satellite. By the joint retrieval of the multi-angle spectral polarimetric information of atmospheric aerosol, the influences of earth surface reflection can be elimated and the accurate detecting outcome is gotten. Thus it is quite urgent to study the integrated optical instrument with the ability to detect multi-angle spectral-polarimetric information of target. The optical system of multi-angle imaging spectropolarimeter was designed, the fore telescope was composed of multi mini-lens, which realized the multi-angle detecting in range of 60long the orbit. The spectroscope system was a common Offner imaging spectrometer. The analysis of imaging quality shows that the MTF of middle waveband at Nyquist frequency is higher than 0.8, and the spot diagrams are all smaller than the Airy disk. All indexes satisfy the commands of system. This optical system is compact in size without any moving part, and can realize the detection of multi-angle polarization state, spectral information and intensity of target.