A familiar term to users of lighting design and analysis software programs,  Bi-directional Scatter Distribution Function (BSDF) is a mathematical table which determines the probability that a specific ray of light will be scattered at a given angle. As a courtesy to our customers, the following BSDF, BRDF and BTDF (Reflected and Transmitted portions of BSDF) data can be imported into Zemax or Optis to help designers and engineers choose the right Luminit Light Shaping Diffuser for the job. If you experience any problems downloading the files, contact: sales@luminitco.com