Comparison and research for several bi-directional reflectance distribution function (BRDF) measuring

The characteristics of spatial light scattered from optical material surfaces are effectively described by BRDF. There are two forms for measuring BRDF: they are absolute measuring and relative measuring. The absolute measuring includes the definition method and introducing bi-directional reflectance factor beta method. The relative measuring includes the substitution method and single reference measuring method. The measuring methods based on vary principles are comprised and the features of each method are analyzed, a set of system based on personal computer for BRDF measuring has been developed, it is made of optical path, electronic path, and mechanical path. With He-Ne laser and YVO4 Solid laser, the measurements on 1500 CCR/RC.S.G Silicon carbide abrasive paper have been made within the -55degrees-55degrees of reflectance zenith angle, the experimental results show that it has better Lambertian diffusion characteristic.