Fraunhofer Institute of Optronics, System Technologies and Image Exploitation IOSB 
The automated gonioreflectometer allows optical reflection measurements in high spatial resolution (BRDF-Bidirectional Reflectance Distribution Function). The light source illuminates the sample from different directions and a robot moves the detector hemispherically around the sample. In each holding position, measurements are taken and statistically evaluated.
The optical scattering behaviour of surfaces is thus recorded in detail. The versatility of the system allows measurements of samples with the most varied material and reflection properties. Diffuse, shiny, specular, smooth, rough, partially transparent surfaces as well as isotropy/anisotropy and retroreflection can be measured in detail.
The measuring system can also be used to measure the spatial light emission distribution of light sources, illuminants, lamps and luminaires.
Technical data:
- sample size: up to approx. 1 m
- sample thickness: up to 30 cm
- measuring surface: > 0.5 cm diameter
- spectral range: VIS, NIR, MWIR, LWIR. wide and narrow band
- angle resolution: 10-4 - 10-3 Steradiant
- retro-reflection measurement possible