The impact of the orientation angles uncertainty of instrument polarizers on polarization measurement accuracy

Abstract

Improving the polarimetric measurement accuracy of the polarization CCD camera is a fundamental task in the remote sensing of the earth. This paper presents a simple approach for estimating the degree of polarization errors caused by the orientation angles uncertainty of the instrument polarizers. We show that the measured degree of polarization error for a certain orientation angle of the instrument polarizers in the same spectral band depends on the polarization state (polarization angle or degree of polarization) of the incident light. In order to evaluate the polarimetric measurement performance of the instrument, the average degree of polarization error is defined based on the assumption that the incident light beams have equal polarization angle probability. The simulated test showed that the average degree of polarization errors of the 3 polarized spectral bands in the airborne polarization CCD camera is nearly equal because of the same orientation angles uncertainty of the instrument polarizers, though the instrument polarizers in the 3 polarized spectral bands are equipped a little differently; the instrument often encounters a large average degree of polarization errors for the large degree of polarization of the incident beams.