Malus and Brewster

In EM-wave, E-field oscillates perpendicular to the propagation.

• Unpolarized wave: E-field oscillates in all possible directions on the plane


• Polarized wave: E-field oscillates along a line (aka linearly or plane polarized)

Polarizer transmits the the component of E-field parallel to its transmission axis. And cuts 50 % of the intensity of unpolarized light.

Malus law: Set the transmission axes of the first and the third polarizers perpendicular to each other. How would you orientate the middle polarizer to have maximum intensity received in the detector? Can you proof it theoretically?

Brewster law: Reflected light is completely polarized if there a right angle between reflected and refracted components. Otherwise it is partially polarized. Rotate the View Angle and take a look to the two components.