Low crosstalk polarization-difference channeled imaging spectropolarimeter using double-Wollaston prism.

A polarization-difference channeled imaging spectropolarimeter (PDCISP) using double-Wollaston prism is presented. It enables simultaneous acquisition of a set of three-channel interferograms corresponding to orthogonal polarization modulation. This brings a large range expanding of optical path difference for useful channels, and the major limitation of channeled spectropolarimetry (CSP), namely the channel crosstalk, can be greatly suppressed by using interferogram difference processing. As a result, full resolution intensity spectrum, as well as high-resolution polarimetric signatures, can be obtained with fewer reconstruction errors, compared to conventional CSP-based systems. The PDCISP is insensitive to alignment errors of retarders and maintains the snapshot feature (1D spatial imaging). The effectiveness of the proposed method is demonstrated by the simulation results.