Physics-based polarimetric BRDF models

Through the use of measurements and analysis we have devised a series of physics-based analytic models for the BRDF that describe the differential polarization of light scattered from a random rough surface. These models incorporate both intrinsic (refractive index) and extrinsic (statistical moments of the surface height variations) properties of the surface as well as wavelength dependence. Detailed surface statistics are acquired with a stylus scanner. Physical optics theory relates these statistics (and thus the complex coherence factor of the fields at the surface) to the far-field intensity of the scattered light. An outcome of these models is the ability to predict the spectrally varying differential polarization of emittance. Excellent agreement between measured and modeled BRDF’s is demonstrated.