Investigation of the misalignment sensitivity of a birefringence-compensated two-rod Nd:YAG laser system

A system for the compensation of thermally induced birefringence in laser rods that consists of two identical Nd:YAG laser rods, a telescope to image the principal planes of the rods onto each other and a 90 degrees quartz rotator to change the state of polarization between the rods has been set up, and its sensitivity to transversal and longitudinal misalignment has been investigated experimentally. A theoretical model to describe the increase of depolarization that is due to misalignment has been developed and compared with the experimental results.