Ultraviolet BRDFs of selected materials

Ball Aerospace is currently designing and building several instruments with strict stray light requirements in the ultraviolet (UV) region. Available BRDF data in this spectral region is very limited, so Ball modified a UV monochrometer to measure the BRDF of critical surfaces. Measurements with the monochrometer were also possible in the visible, so results in the visible were compared to results using a TMA scatterometer. Results from the two instruments compared reasonably well and were used to generate correction factors for the UV BRDF data. Surfaces measured included Graphite Fiber Reinforced Cyanate (GFRC), Desoto Black paint on GFRC, Spectralon, and an aluminum diffuser.