Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle.
Applicable units are those of quantitykind:Luminance
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Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through or is emitted from a particular area, and falls within a given solid angle.
$L_v = \frac{dI_v}{dA}$, where $dI_v$ is the luminous intensity of an element of the surface with the area $dA$ of the orthogonal projection of this element on a plane perpendicular to the given direction.