Stress-induced birefringence of solids transparent to 1- to 12-μm light

Abstract

The application of a variation of intensity method using static uniaxial compressive stress and polarized light to measure stress-induced birefringence in the infrared wavelength region (?1 to 12 μm) is described. The measurements were made at 296 °K for the following materials: KCl, KBr, KI, NaCl, LiF, ZnS, ZnSe, SrF2, CaF2, MgF2, and a chalcogenide glass TI-1173; for the alkali halides the values of the stress optic coefficients obtained are in the range ∼1–4 Brewsters, while for the nonoxide glasses values of 9–14 Brewsters were measured. Comparisons of measurements from experiments with a theoretical model which predicts the wavelength dispersion of stress birefringence cannot be fitted better than a factor of ∼2.