同时偏振成像系统可获取动态物体的瞬态偏振特性,具有广泛的应用前景。然而各偏振探测通道存在空间和辐射响应差异,对准确建立仪器穆勒矩阵造成干扰。针对分束型同时偏振成像系统,分析了误差来源,提出了定标及预处理方法。通过成像非均匀性、辐射响应不一致性、检偏角度误差、瞬时视场像差的标定和校正,消除了偏振成像探测的系统误差。结果显示:经过定标和校准处理,各通道图像非均匀度平均降低了2.24%,辐射响应差异率绝对值平均降低了17.22%,偏振相对快轴方向平均纠正了1.71°,成像几何偏差平均纠正了1.87个像元。校正后,系统偏振度和偏振角测量误差分别降低0.47和32.84°。对室外场景进行测量实验,经过预处理正确解算斯托克斯参量,并通过偏振图像融合处理,突出了不同材质的物性差异。

The simultaneous imaging polarimeter can obtain the transient polarization characteristics of moving objects, and it has a wide application prospect. However, the polarization detection channels differ in spatial and radiation response, which interferes with the accurate establishment of the instrument Muller matrix. The system error source is analyzed, and the calibration and preprocessing method is proposed for the amplitude divided simultaneous imaging polarimeter. The system error of polarization imaging detection is eliminated by the calibration and correction of non-uniformity of detectors, inconsistency of radiation response, deviation of polarizers oriented angles, and difference of instantaneous field of views. The results show that after the calibration and preprocessing, the CCD non-uniformity of every channel decreases by 2.24% on average, the absolute values of radiation response differences ratio decrease by 17.22% on average, the actual polarizer oriented angles are corrected by 1.71° on average, and the imagery pixel offsets are corrected by 1.87 pixel on average. After correction, the measurement error of polarization degree and polarization angle decrease by 0.47 and 32.84°, respectively. The outdoor scene is measured and tested, the Stokes parameters are calculated correctly after preprocessing, and the physical characteristics of different materials are highlighted after the polarization imaging fusion.