Measurement of dynamic ellipticity of polarized light and application to the Kerr effect

Abstract

A system for the measurement of time-varying ellipticity and axis orientation of polarized light has been developed and specifically applied to the analysis of the birefringence of macromolecular solutions in a Kerr electro-optic cell. The method of measurement is based upon the passing of the elliptical light through a rapidly rotating analysing prism, ahead of photodetector. When elliptical light results from the passage of circularly polarized light through a material having slowly changing birefringence and optical axis orientation, these material properties may be continuously monitored. In the application of the Kerr effect, the steady and alternating components of the birefringence are separated in the frequency domain of the photodetector output. The measurement system provides a high degree of discrimination against problems due to light intensity variations and small residual birefringence in Kerr cells.