Interferometric determination of optical anisotropy in fibers 1‐ homogeneous fibers

This article describes a method for the measurement of refractive indices and birefringence of fibers. It is used to overcome difficulties in measuring refractive indices of immersion liquids as well as the corrections for dispersion and temperatures. Two fibers are used for each measurement. One is of known refractive index and dispersion properties and the other is of unknown refractive index. A modified mathematical formula is used with a two‐beam interference microscope. This technique is applied to two groups of fibers having different ranges of refractive indices. The first group contains seven different products of nylons and the second group contains five different products of polyesters. The calculated refractive indices using this method is compared with those obtained using the established method. Illustrations are given using microinterferograms.