Design of polarimetric BRDF measurement system based on configuration of dual rotation retarder

Polarization BRDF can be used to describe the space distribution of radiation intensity of objects and it includes plenty of polarization information. Compared with the scalar BRDF, the polarimetric BRDF can show the light scattering of an object surface more accurately and completely．A polarimetric BRDF measurement system based on dual rotating retarder configuration was designed. The polarization state of incident and scattering light was modulated by synchronously rotating wave plates to acquire a series of changing light intensity. The polarimetric BRDF of the sample was obtained by calculating the Fourier decomposition coefficients of the light intensity. A pair of orthogonal mirrors were mounted in the system to minimize the influence of back-scattering light from some other components in the system. The precision of measurement system was demonstrated by the measurement result of the aluminium-plate polarimetric BRDF.