Radiance

	Main Article	Discussion	Related Articles  [?]	Bibliography  [?]	External Links  [?]	Citable Version  [?]
	This editable Main Article is under development and subject to a disclaimer. [edit intro]

Radiance is a term in radiometry. It is defined as:

${\displaystyle L=\frac{d^2\mathrm{\Phi }}{dAd\mathrm{\Omega }cos\theta }}$

Where ${\displaystyle \mathrm{\Phi }}$ is radiant flux, ${\displaystyle A}$ is an area, and ${\displaystyle \mathrm{\Omega }}$ is a solid angle.

Typical units are ${\displaystyle [\frac{W}{m^{2}sr}]}$ where "sr" means steradians.