Estimation theoretic framework for comparing polarization based, continuous-wave direct imaging schemes

We report a maiden study and comparison of two important classes of polarization based continuous-wave optical imaging schemes for imaging through scattering media, namely, the polarization difference imaging (PDI) and the polarization modulation imaging (PMI). We cast the problem in an estimation theoretic framework and base the comparison on two visualization parameters, the polarization magnitude and the degree of polarization. We show that PDI is superior in estimating these two parameters in active imaging. However, we show that PMI is suitable for passive imaging and that the PDI is a specific implementation of PMI.