Birefringence simulations of annealed ingot of calcium fluoride single crystal by considering creep behavior of ingot during annealing process

We developed an analysis system for simulating birefringence of an annealed ingot of CaF₂ single crystal caused by the residual stress after annealing process. In the residual stress calculation, we can select either the elastic thermal stress analysis using a stress-free temperature or more exact stress analysis considering creep deformation. When we use the residual stress calculated from the creep deformation analysis of a CaF₂ ingot, we can obtain reasonable results in comparison with the experimental results.