Analysis of Elliptical Polarization

In order to analyze an elliptical light wave, we must find its state of polarization which is completely determined by three parameters, i.e., the direction (azimuth), the form (ellipticity), and the sense of the ellipse described by the light vector. In this paper a survey is given of the direct and indirect methods used for the measurement of the magnitudes of the three parameters. First, a mathematical treatment, which uses the calculus of quaternions, of the state of polarization for special cases will give the background to the theories of the methods discussed.