Bi-hemispherical reflectance is the
reflectance
The reflectance of the surface of a material is its effectiveness in Reflection (physics), reflecting radiant energy. It is the fraction of incident electromagnetic power that is reflected at the boundary. Reflectance is a component of the respon ...
of a surface under
diffuse illumination (with no direct component). Bi-hemispherical reflectance is an important part of the
Bidirectional reflectance distribution function
The bidirectional reflectance distribution function (BRDF; f_(\omega_,\, \omega_) ) is a function of four real variables that defines how light is reflected at an opaque surface. It is employed in the optics of real-world light, in computer ...
over all viewing and illumination directions of a hemi
sphere
A sphere () is a Geometry, geometrical object that is a solid geometry, three-dimensional analogue to a two-dimensional circle. A sphere is the Locus (mathematics), set of points that are all at the same distance from a given point in three ...
.
It is sometimes called "white-sky albedo".
See also
*
Directional-hemispherical reflectance Directional-hemispherical reflectance is the reflectance of a surface under direct illumination (with no diffuse component). Directional-hemispherical reflectance is the integral of the bidirectional reflectance distribution function over all viewin ...
References
Electromagnetic radiation
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