Simultaneous measurement of birefringence magnitude and direction using Wo llas ton prism

摘要

Simultaneous measurement of the birefringence magnitude and direction using Wollaston prism is presented. The sinusoidally modulated laser beam passes through a circular polarizer, the birefringence sample and is split by a Wollaston prism. The measuring beam is then detected by a bi-cell detector and two alternating current signals are detected. Then the Wollaston prism is rotated by 45°, and another two alternating current signals are obtained. By processing the four signals, the birefringence magnitude and direction is resolved simultaneously. In experiments, a wedge waveplate was laterally moved and measured at different birefringence magnitude. The measured birefringence magnitude linearly increased as the wedge waveplate was laterally moved. The maximum standard deviation of the birefringence magnitude and direction is 0.11° and 0.05°. The usefulness of this method is verified.