Application of immersion reflectometry to the study of interference layers.

The reflectance of a thin film changes upon immersion in a transparent dielectric liquid. By use of spectrophotometry, the changes in reflectance at the wavelengths where maximum or minimum reflectance occurs have been characterized for a variety of optical combinations including both transparent and absorbing films and substrates. The complications and ambiguities of interpretation for each system and the effects of multilayer structure have been examined.

Strain-Induced Birefringence in Fluoride Films on Uranium Dioxide.

Optically birefringent microstructures are formed within fluoride films that are produced on uranium dioxide by hydrofluorination. The positive molar volume change of the reaction produces nonuniform tensile and compressive stresses around sites of surface roughness which result in optical double refraction.