Crosstalk-Analysis of a Hybrid Division of Aperture/Division of Focal-Plane Polarimeter

Development of optical micro electro mechanical systems make it possible that the micro polarizing elements can be integrated on the focal plane array. The imaging polarimetry based on this method is called imaging polarimetry through the division of focal-plane array. As the pixels that are used to infer the polarization information corresponding to different points in the object, the above method has an intrinsic error. Tyo [OPTICS LETTERS, 31(20): 2984-2986] solved this problem through hybrid division of aperture/division of a focal-plane. An improvement of Tyopsilas method is presented in this paper. A baffle is used to reduce crosstalk in the sampled sub-image of the micro-lens array. The effect of the position, form, size of the baffle and the parameters of the sampling micro-lens array on the crosstalk are discussed. The results show that inter-unit crosstalk behind the image-sampling micro-lens could be suppressed through properly set baffle in a distance, which changes conversely with the image area being sampled. Intra-unit crosstalk could be reduced by the decrease of the angle between the light rays and the optical axis. This reduction is based on the decrease of the intermediate image area being sampled.