Absolute radiation and polarization combined calibration method and device

The invention provides an absolute radiation and polarization combined calibration method and device which can perform high-precision absolute radiation calibration on a channel dispersion type polarization spectrum imager, improve the polarization detection precision of the channel dispersion type polarization spectrum imager and realize the unification of the polarization detection precision ofdifferent fields of view. In an absolute radiometric calibration process, an influence of a polarization effect of a front lens group is considered, inevitable azimuth angle errors of two phase retarders and phase factors of different fields of view are calibrated, and the influence of the polarization effect and the azimuth angle errors of the front lens group on the absolute radiometric calibration and detection results of the instrument is eliminated. Polarization detection precision of the instrument can be effectively improved, and the polarization detection precision of different fieldsof view is unified. The me