# 17-24-049

scattering

diffusion

process by which the spatial distribution of a beam of radiation is changed when it is deviated in many directions by a surface or by a medium, without change in frequency of its monochromatic components

Note 1 to entry: A distinction is made between selective scattering and non-selective scattering according to whether or not the scattering properties vary with the wavelength of the incident radiation.

Note 2 to entry: The frequency is unchanged only if there is no Doppler effect due to the motion of the materials from which the radiation is returned.

Note 3 to entry: This entry was numbered 845-04-44 in IEC 60050-845:1987.

Note 4 to entry: This entry was numbered 17-1139 and 17-311 in CIE S 017:2011.

Publication date: 2020-12