This experiment starts with the investigation of Malus’s law, which states that transmittance of a linear polarized light through a polarizer is the square of a cosine of the relative angle between the polarization direction and the transmission axis of the polarizer.
In the second part of the experiment, one employs a half-wave plate to rotate the polarization direction of a linearly polarized laser beam and a quarter-wave plate to produce elliptically and circularly polarized light. The transmission and reflection of light from a material depends on the polarization of the incident light. In this experiment, one measures the intensity of reflected light from a glass material upon which a p- or s-polarized laser is incident. From the measured data, the Brewster angle of a p-polarized incident laser on a glass can be determined.