Effect of distortions on spectral signal acquisition of the grating imaging spectrometer

Abstract

The grating imaging spectrometer has the characteristics of good linearity, wide dispersion range and is widely used in the field of remote sensing. Distortions (including smile and keystone) are one of the important parameters of the grating imaging spectrometer, which directly affects the quality of the image and spectral information obtained by the imaging spectrometer. In order to get the requirements of two kinds of distortions in the design process of the grating imaging spectrometer, the effect of the smile and keystone on the target detection is simulated and analyzed respectively. Based on the spectral response function with the Gaussian, the change of the spectral signal acquired by the grating imaging spectrometer with the amount of the different smile is calculated by combining with the spectral data of the atmospheric in the visible and near-infrared (0.4~1μm). The results show that the amount of smile should be no more than 1nm, 0.6nm and 0.2nm respectively when the spectral resolutions of the imaging spectrometer are 20nm, 10nm and 5nm. With the assumption that the spatial response function is the rectangle function, the effect of the different keystone on spectral signal acquisition of the imaging spectrometer is simulated by using the hyperspectral data. The results indicate that the offset of the keystone should be controlled within 0.04d (d is the pixel width).