Measuring the BRDF and radius of curvature with patterned illumination
Shinichi Inoue, Norimichi Tsumura · OSA Continuum · 2021
In this study, we propose a method to measure simultaneously the bidirectional reflectance distribution function (BRDF) and the radius of curvature of a curved surface. The surfaces of pre-molded products or artworks are not always flat. The measurement targets were a planar surface and convex surfaces with constant radiuses of curvature. We developed and experimented with an apparatus that uses patterned illumination and a collimator optical system. The results show that BRDF and radius of curvature can be measured on a curved surface. In future work, we are developing a method to accurately estimate the BRDF of a planar surface from the measured BRDF and radius of curvature.