Angle-Resolved Spectrophotometry for the Optical Characterization of Material Surfaces

Surface reflectance is a practical metric of the optical performance of a material. Applications, such as glass manufacturing, light sensing, satellite reflectors, and photovoltaics, depend on their reflectance properties and generalized optical performance. Reflectance measurements are rarely reported comprehensively, with only a single angle of incidence common in most datasets. Here, we present a new spectrophotometry system capable of performing angle-, wavelength-, and polarization-resolved reflectance measurements on various surfaces. Data from such a system yields significant information regarding the everyday, real-world performance of said materials. We perform exemplar studies by characterizing several standard thin-film antireflectance coatings and comparing the results to their known theoretical optical response. We also present results from measurements on an optical insulating material as well as a selection of wall paints to showcase the versatility of the technique. We highlight the parallels between measurement and theory, while analyzing the realistic implications of the measurements on their respective material’s practical performance under real-world conditions.