The structure of the polarization detector is introduced firstly, the signal response model of the detector is established. Based on the signal response model, the corresponding parameter calibration scheme is made. High-precision calculation of polarization states of incident radiation and non-uniformity correction of polarization image are realized. The experimental data show that the calculated linear polarization is 97.8% ~ 101.5% of the true value after calibration, which meets the accuracy requirements of polarization detection. The non-uniformity of intensity image and linear polarization image has been reduced by 93.64% and 93.67% respectively compared with the uncorrected image, and the image quality has been effectively improved.