BSDF: Bidirectional Scattering Distribution Function


The BSDF setup allows the spectral measurement of the angular reflection and transmission pattern of a material under different irradiation geometries.

The setup consists of two parts: the irradiation section and the detection section. The irradiation section consists of a Xe lamp (250 W). Using a collimating mirror, a parallel beam is created, which is directed towards the sample. A filter wheel with neutral density filters can be inserted in the path of light to enhance the dynamic range of the setup. The sample is positioned in a sample holder, which allows rotation around two axes (vertical and horizontal). This allows the selection on any incident direction of the beam on the sample. The detection part consists of a bench which can be rotated (using stepper motors) around two axes. This allows the selection of any viewing angle. A detector is positioned at the end of the bench, which is connected to a spectrometer with CCD with an optical fiber.


  • Xe light source (250 W)
  • Filter wheel with 3 neutral density filters, dynamic range > 6 decades
  • Full 3D range (reflection and transmission)
  • Angular resolution: 1.8°
  • Spectrometer with CCD: spectral measurements
  • Wavelength range VIS CCD: 360-800 nm
  • Wavelength range NIR CCD: 800-1300 nm
  • Spectral bandwidth: 3.5 nm
BSDF setup
Detail of the BSDF setup
Detail of the BSDF setup
The bench with detector