Meaning of Malus' law

Ma•lus'' law'

Pronunciation: (mu-ls' Fr. ma-lys'), [key]
— Optics. Optics.
  1. the law stating that the intensity of a beam of plane-polarized light after passing through a rotatable polarizer varies as the square of the cosine of the angle through which the polarizer is rotated from the position that gives maximum intensity. Also called
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.