APPLICATION OF MULTIPLE-BEAM WHITE-LIGHT FRINGES FOR MEASURING THE REFRACTION AND DISPERSION OF MICA

Multiple-beam white-light interference fringes are applied to measure the two refractive indices of a mica sample and their dispersion acros s the visible spectrum. In addition, the mica birefringence and its di spersion are measured. A mica sample of dimensions 2 x 5 mm(2) and an immersion liquid of nearly the same refractive index are used. Only a single shot interferogram is needed to measure all the aforementioned parameters. Cauchy's and a modified single-term Sellmeier dispersion f ormula are used for fitting the experimental data and extracting the p arameters required. (C) 1997 Elsevier Science Ltd. All rights reserved .