Thin-film approximate modeling of in-core fiber gratings
Abstract
Generally tilted in-core fiber gratings are modeled by an equivalent inhomogeneous optical thin film. Its reflectance spectrum is evaluated using the multilayer and optical-path approximations. The results are shown to be similar to those obtained using the exact local-normal mode method for the case of weak gratings. A fiber grating synthesis procedure is also introduced based on the methods advanced in this paper.