Determination of the optical constants of MgF(2) and ZnS from spectrophotometric measurements and the classical oscillator method.

The values of the optical constants of magnesium fluoride (MgF(2)) and zinc sulfide (ZnS) thin films are obtained using a classical oscillator model and the experimental values of their spectral transmittance. Auger electron spectroscopy was performed on the samples to determine the chemical composition of the films. These materials are important in the design of filters, mirrors, and antireflection coatings for optical instrumentation. Unfortunately their properties strongly depend on evaporation conditions. The procedure described here allows direct measurement of the dispersive refractive index of the film after deposition.