Malus Law
Malus Law
the dependence between the intensity of linearly polarized light after its passage through an analyzer on the angle a between the planes of polarization of the incident light and the analyzer. It was established by E. L. Malus in 1810. If I0 and I are the intensities of the light incident on and leaving the analyzer, respectively, then according to the Malus law, I = I0cos2 a. Light with a different (nonlinear) polarization can be represented in the form of the sum of two linearly polarized components, each of which obeys the Malus law. The intensities of transmitted light in all polarization instruments, such as polarization photometers and spectrophotometers, are calculated by the Malus law. Losses to reflection, which are a function of a and are not taken into account by the Malus law, are determined in further calculations.