Modeling and Characteristic Analysis Methods for Reflection Polarization on Coated Surfaces

To study the polarization characteristics of light reflection from coated surfaces, this paper proposed a modeling method based on the Monte Carlo method for the polarized bidirectional reflectance distribution function (PBRDF). Specifically, Fourier transform was performed for the three-dimensional reconstruction of a coating- substrate double-layer rough surface. Then, the microfacet theory and the Fresnel equation were employed to solve the processes of stochastic reflection and refraction from a single facet, and the process of polarized light scattering on the reconstructed surface was statistically summated by the polarization ray tracing technique and the Monte Carlo method to obtain the PBRDF of the coated surface. Experimental results show that the PBRDF built by the proposed method is correct and the proposed model outperforms the existing models in accuracy. Finally, the effects of the incident angle, surface roughness, substrate material, and optical thickness of the coating on the polarization characteristics of light reflection from the coated surface are analyzed to provide a theoretical basis for the detection and measurement of coated surfaces.