Demodulation of polarization information for a spatially modulated snapshot imaging polarimeter based on the coherent demodulation theory

The snapshot imaging polarimeter (SIP) using spatial modulation can obtain all the Stokes parameters of the target through a single measurement. During demodulating of the polarization information of the target, the reference light calibration method is generally used, including a bandpass filter. In this work, a method to demodulate the target polarization information is proposed, which is based on the coherence demodulation theory. Additionally, this method includes a multiplier and a low-pass filter. Taking a spatially modulated SIP using modified Savart polariscopes as an example, a detailed theoretical analysis of the method is derived, and the computer simulation and experiments are carried out to verify the method’s feasibility. To the best of our knowledge, this work provides a novel method for demodulating polarization information of spatially modulated SIPs.