Spatially modulated snapshot imaging polarimeter using two Savart polariscopes.

We present a spatially modulated snapshot imaging polarimeter using two Savart polariscopes (SMSIPTS). Not only can it avoid alignment angle errors and additional phase errors of a half-wave plate (HWP), it can also avoid changing the HWP frequently when we want the target polarization state at different wavelengths and can increase some channel bandwidth to improve image quality, compared with a spatially modulated snapshot imaging polarimeter (SMSIP). The alignment angle error and additional phase errors of SMSIP and the optical layout and principle of SMSIPTS are derived first. The full Stokes polarization images can be obtained by processing the interferogram. Based on SMSIPTS, we determine the filtering method by simulation. We proved the feasibility of SMSIPTS, and the effect of SMSIPTS and SMSIP on reconstruction is compared by simulation. Last, we experimentally verified the feasibility of the theory of SMSIPTS.