Performance comparison of division of time and division of focal plan polarimeters

Two typical instruments can be employed for linear polarization imaging: a rotating polarizer in front of a classical monochrome camera (division of time), or a dedicated sensor with a polarization filter array (division of focal-plane). The last method enables the snapshot acquisition of the linear polarization properties of the light with a compact and affordable instrument. The rotating polarizer method has until now been preferred when good polarimetric precision is required. It is still unclear how these two techniques perform comparatively in terms of polarimetric accuracy. This paper provides a practical comparison between the two methods, and evaluates the effect of pre-processing applied on raw images to counterbalance the differences.