A synchronous multi-angle scattered light field measurement system is constructed in this study to overcome issues with current systems in the field of multi-angle remote sensing. A mathematical model of the scattered light field measurement was established. An off-axis catadioptric optical system was designed to satisfy hemispheric spatial scattered light field measurements in a zenith angle range of 68°. The off-axis calibration model was established, and the spatial relationship was calibrated. The measurement accuracy was calibrated via an integrating sphere light source, and the maximum measurement relative error was − 3.71 % . The scattered light field of the reference diffuse reflective target plate Labsphere Permaflect-50 and 304 stainless steel was simulated under an incident light irradiation range within the zenith angle of − 23.5 ∘ to + 23.5 ∘ , and synchronous measurement of the multi-angle scattered light field of the sample was realized. The measurement system could provide technical support for building the complex model of multi-angle reflection/radiation from the earth’s surface, multi-angle sensor radiation calibration, and improvement of the physical parameter inversion accuracy of observation targets.

The bidirectional reflection distribution function (BRDF) is among the most effective means to study the phenomenon of light–object interaction. It can precisely describe the characteristics of spatial reflection of the target surface, and has been applied to aerial remote sensing, imaging technology, materials analysis, and computer rendering technology. This study provides a comprehensive review of the development of devices to measure the BRDF. We gathered research in the area by using the Web of Science Core Collection, and show that work on the BDRF has been ongoing in the last 30 years. We also describe some typical measurement devices for the BRDF proposed in the literature. Finally, we summarise outstanding problems related to BRDF measurement and propose directions of future research in the area.

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