White-light spectral interferometry and its applications in fiber optics

摘要

In this contribution, an overview of applications of white-light spectral interferometry in dispersion characterization of optical fibers is presented. First, spectral-domain intermodal interference is analyzed theoretically at the output of a few-mode optical fiber alone and at the output of the optical fiber in a tandem configuration with a Michelson interferometer. The theoretical analysis is performed under general measurement conditions when a broadband source and a spectrometer of a Gaussian response function are considered and when the first-order and second-order intermodal dispersion effects in the optical fiber are taken into account. Second, the theoretical analysis is performed for three different examples of dispersion curves of two-mode optical fibers and the effect of the limiting factors is specified. Finally, the theory is accompanied by the corresponding experiments for measuring either the intermodal dispersion in circular-core and elliptical-core fibers or the dispersion of birefringence in the elliptical-core fiber.