Thermal Coefficient of Refractive Index of Polycrystalline ZnSe, BaF2and CaF2in the Visible and Near Infrared.

摘要

An interferometric technique has been used to measure the thermal coefficient of the refractive index of polycrystalline ZnSe, BaF2, and CaF2 at the HeNe laser wavelengths, 0.6328, 1.15, and 3.39 micrometers, in the range 25 -65C. The values obtained were calculated using the observed change in optical path and the literature values for refractive index and thermal expansion coefficient.