A Scheme for High Spatial Resolution Imaging Spectroscopy Technology

Imaging spectrometers with high spatial resolution and high spectral resolution have low signal to noises ratio(SNR). In order to improve SNR, satellite scanning-back scheme is adopted to improve the integration time of the system and reduce the requirement for large aperture optical system with high spatial resolution. The imaging spectral technology scheme with orbital height of 500 km, swath of 10 km, spatial resolution(GSD) of 1 m, spectral resolution 5 nm, wavelength range of 0.4–1.0 um and SNR of no less than 100 is proposed, and the optical system is designed. The front telescopic system consists of a folded axis three mirror structure a focal system and an inverse Cassegrain structure objective lens system. The 4 m aperture beam is compressed into 250 mm for imaging, with an F/1.375, a field of view (FOV) of 1.146°, and an image slit length of 110 mm. The spectroscopic system consists of two Dyson optical structures, with a single slit length of 55mm, and two splice covering the front system’s slit of 110 mm.