Keywords: Lambert Cosine Law 2.svg en A diagram showing observed intensity from a Lambertian surface; units photons/ s·cm<sup>2</sup>·sr for a normal and off-normal observer; dA<sub>0</sub> is the area of the observing aperture and d is the solid angle subtended by the aperture from the viewpoint of the emitting area element Own Inductiveload 2008-11-27 Lambert's cosine law |