bi-directional reflectance distribution function
BRDF
function describing the change with direction of irradiation, (, with respect to the irradiance incident on the medium from the given direction of irradiation at the given wavelength,
:
Note 1 to entry: The bi-directional reflectance distribution function is expressed in steradian to the power minus one (sr−1).
Note 2 to entry: See also "radiance coefficient".
Note 3 to entry: This entry was numbered 17-87 and 17-109 in CIE S 017:2011.