Using the MSL goniospectrophotometer to measure the bidirectional transmittance distribution function

Abstract Measurements of the bidirectional transmittance distribution function (BTDF) are of interest to a wide range of industries, including satellite calibration, computer graphics, and lighting design. The scale of BTDF is realised at various national metrology institutes using goniospectrophotometers. This paper describes the measurement model for BTDF using the MSL goniospectrophotometer, which uses rotation stages to adjust the angle of the sample. The measurement model is applied to measurements of two different sample types as an example of the performance of the instrument.