Some approximate relations in the photoelasticity of strongly anisotropic crystals

Abstract

The knowledge of the principal refractive indices and their dependence on the applied stress is the starting point for any experimental analysis of transparent crystals. Because for strongly anisotropic crystals and a general state of stress an explicit analytical solution can be difficult to obtain, then we need some approximated solutions. Here, we propose a coherent approximation procedure that generalizes results already obtained and give a simple example of application.