Infrared BRDF measurement based on projection reconstruction with attenuated aperture filter effects

Abstract

The Bidirectional Reflectance Distribution Function (BRDF) is a basic function that describes the spatial reflectivity of an opaque surface. Existing BRDF measurements are related to the size of the detector aperture because the values are not the true BRDF but an average over the aperture, and high spatial resolution and high SNR cannot be achieved simultaneously. In addition, the detection positions of the aperture cannot perfectly cover the entire hemisphere, and the measurement is not complete. In this paper, BRDF measurements were combined with projection reconstruction, and the mapping between the detected signals and the BRDF over a discrete hemispherical mesh was constructed. The spatial resolution of the reconstruction was the same as that of the discrete mesh, rather than the aperture size, and the aperture filter effect was attenuated. Simulations and a frosted gold plate measurement experiment were performed to verify the effectiveness of the proposed reconstruction method.