Efficient calibration method of total polarimetric errors in a channeled spectropolarimeter

An efficient calibration method of total polarimetric errors in a channeled spectropolarimeter (CSP) is proposed and experimentally demonstrated. Total polarimetric errors, including alignment and retardance errors as well as those caused by nonideal retarders and the polarizer in CSP, are considered and calibrated. We first construct the calibrated modulation matrix of CSP by directly measuring the Mueller matrix spectrum of the polarization module in CSP. Compared to previously reported calibration works that required 1074 measurements, our calibration requires only 16 individual measurements, which reduces the measurement time by 67-fold while ensuring high accuracy with a maximum rms error less than 0.02. Further experimental test on three types of different CSP systems confirms the efficiency, reliability, and accuracy of the proposed calibration method.