Optical system design of an unmanned airborne greenhouse gas imaging spectrometer

In this paper, the optical system of an unmanned airborne greenhouse gas hyper-spectral imager that can be used for greenhouse gases is presented. The spectrometer adopts a self-collimating Offner structure. The telescope system adopts the image square telecentre structure. The spectral resolution is improved to more than 0.2 nm by image merging, and the signal-to-noise ratio is better than 200 at an integration time of 1 s at the simulated incident pupil brightness.