Crosstalk model of division of focal plane polarization cameras: optical causes and parameter effects

The division of focal plane polarization cameras is a widely used integrated polarization imaging system, where light intensity crosstalk between micro-polarizer pixels introduces measurement errors. Previous studies have only assessed qualitative crosstalk trends. Here, we model crosstalk as near-field, non-paraxial diffraction of an ideal metal grating. Using the angular spectrum method with spatial-domain discrete sampling, we establish how the F-number and incident angle influence crosstalk intensity distribution. We analyze coherence effects and propose a cosine-based intensity response. Macroscopic experiments validate our microscopic model, revealing polarization parameter deviations and system noise, confirming crosstalk calibration feasibility.