Malus cosine-squared law

Malus cosine-squared law

[′mä·ləs ¦kō‚sīn ′skwerd ‚lȯ]
(optics)
The law that if a beam of plane polarized light passes through a Nicol prism, the intensity of light emerging from the prism is proportional to the square of the cosine between the plane of polarization of the incident light and the plane of polarization of the prism.