The measurement of scattering losses in thin dielectric films

Abstract

When a bounded wave is incident on an interface from the denser medium and at critical incidence, a lateral wave is propagated along the surface. This offers the possibility of a new and powerful method for the study of the optical homogeneity of interface regions. In this work, the method is used for the study of scattering loss in dielectric films. A second method, which employs waveguide modes propagated in the film, is also explored. Measurements are supplemented by scattering studies with use of an integrating sphere. The dependence of scattering losses on the conditions of deposition of magnesium fluoride and zinc sulphide films has been investigated.