ABSTRACT
The most general polarized vibration is elliptic. Frequently the orientation of the vibration to be analysed is known a priori. The determination of the ratio of the axes and the sense in which the ellipse is described is equivalent to the determination of the variations in the orientation of a linear vibration by the method of quarter-wave plate. If the vibration passes through a quarter-wave plate whose neutral lines coincide with the axes of the ellipse, it is transformed into a linear vibration. By trial and error the orientations of the quarter-wave plate and the analyser are so adjusted that the neutral lines of the quarter-wave plate are parallel to the axes of the ellipse and the vibration is stopped by the analyser.
