Mirror-attenuator-mosaic diffuser performance

The diffuse radiance outgoing from mirror-attenuator-mosaic diffusers is with in certain limits independent from the angle of the incident light. Such diffusers are useful as calibration sources for the Scanner for Radiation Budget radiometer and for similar purposes as well. Two techniques of production of directional diffusers (etching and diamond drilling) are compared. To measure the performance of the samples, a new measurement setup is introduced that permits the direct comparison of incoming and outgoing light with an accuracy of better than 0.5%. The diamond drilling technique shows a much better performance than the etching.