Calculation of Stokes vector of laser backscattering from typical geometric rough surfaces at a long distance

The polarization bidirectional reflectance distribution function is key to establishing the relationships between incident and backscattering Stokes vectors. For analytical calculation of Stokes vectors of backscattering light from rough surfaces of objectives at long distances, we treat complicated objectives as a combination of several typical geometric surfaces. The analytical calculation forms of Mueller matrices of typical geometric rough surfaces at different sizes and geometric parameters are presented using a microfacet model, and thus, the backscattering Stokes vectors are determined. Experimental results of four types of geometric forms show good agreement with theoretical simulation, except when the incident angle is larger than about 60° at a wavelength of 532 nm. Further studies should be focused on improving the microfacet model for fitting the experimental results at large incident angles, and effects of multiple reflections between different geometric surfaces cannot be neglected when the combination of typical geometric surfaces is considered.