Mechanical stress birefringence of optical plates.

Modeling the mechanical stress birefringence and slow-axis distributions of optical plates is critical for optical lithography systems. In this paper, the distributions of mechanical stress birefringence and the slow axes of optical plates were modeled by the finite element (FE) model, stress optic relations, and the ray-traced Jones matrices method. To validate this model, the load incremental approach was utilized to reduce the disturbance of residual birefringence in mechanical stress birefringence measurement. The measured distributions of birefringence and the slow axis of the optical plate show a good agreement with our numerical simulation results. This model provides a better understanding of simulation of mechanical stress birefringence and provides a reference for optical design and polarization analysis of other optical elements.