Method for the radial profiling of material dispersion of optical fibers due to mechanically induced optical anisotropy

Abstract

Multiple-beam Fizeau fringes are applied to study the effect of pure mechanical bending on some of single-mode optical fiber parameters. The induced birefringence and the associated radial refractive index profiles are measured as a function of fringe shift in case of very sharp radii of curvature. For the first time, the measured variation in index profiles incorporation with the minimum variance technique are employed to study some important parameters such as the oscillation energy, dispersion energy, and lattice energy profiles of the fiber cladding material predicting their radial variation with bending. The material dispersion profiles are specified as a function of the evaluated variations of the radial profiles of the oscillation and dispersion energies, respectively. The presented method provides an accurate study of the fiber parameters and their variations due to external effects, avoiding at the same time the complications of the dispersion measurements. Microinterferograms are given for demonstration. © 2006 Society of Photo-Optical Instrumentation Engineers.