WAVE-PROPAGATION THROUGH A MEDIUM WITH STATIC AND DYNAMIC BIREFRINGENCE - THEORY OF THE PHOTOELASTIC MODULATOR

A theoretical analysis is given of the propagation of a linearly polarized electromagnetic wave through a medium with a harmonically oscillating birefringence and a static birefringence whose principal axis is inclined to the oscillation axis. The theory is applied to the photoelastic modulator (PEM) to predict the transmitted light flux in experimental configurations of particular spectroscopic and polarimetric importance. Included is the general configuration of a modulator between two polarizers (applicable to nearly all PEM-based light-transmission experiments) and the single-polarizer configuration (characteristic of recent experiments to measure natural optical activity by light reflection). Good agreement between observed results not only provides a test of the theory but accounts for recently observed anomalies that are not explicable on the basis of the standard description of the photoelastic modulator. © 1990 Optical Society of America.