diffuser
device predominantly using scattering to alter the spatial distribution of radiation from a source
Note 1 to entry: If all the radiation reflected or transmitted by the diffuser is scattered with no regular reflection or regular transmission, the diffuser is said to be completely diffusing, independent of whether or not the reflection or transmission is isotropic.
Note 2 to entry: Besides scattering, a diffuser can also have a slight reflection and absorption effect.
Note 3 to entry: This entry was numbered 845-10-34 in IEC 60050-845:1987.
Note 4 to entry: This entry was numbered 17-310 in CIE S 017:2011.