Method for Birefringence Measurements with Correction of Errors Due to Multiple Reflection in Anisotropic Plates

Abstract

Birefringence measurements of anisotropic plates using coherent light are affected by errors due to the multiple reflections in the investigated plate. An evaluation method for measuring birefringence is presented, where the intensity distributions of two light beams are used for the correction of these errors. These beams arise from a polarizing beam splitter, which is the analyser of the polarization system. In this paper, a theoretical treatment is given which shows that this method results in more accurate values than the usual methods, especially for highly refractive materials with a small birefringence.