An exact analysis using the Green’s function formulation of an arbitrarily oriented off-axis dipole in a three-layer cylindrical dielectric waveguide is carried out. The practical significance of such a formulation is illustrated by its immediate application to the problem of radiation due to scattering from an arbitrarily located discrete inhomogeneity in step-index fibers in which the dominant HE1 1 mode propagates. For small dielectric differences between the adjacent layers, the analysis yields radiation loss that agrees well with that evaluated from the infinite-medium approximation. However, the spatial distribution of the radiation loss differs markedly from that predicted by the infinite-medium approximation.
© 1980 Optical Society of America
A. Safaai-Jazi and G. L. Yip, "Scattering from an off-axis inhomogeneity in step-index optical fibers: radiation loss," J. Opt. Soc. Am. 70, 40-48 (1980)