A simple analytical solution for loss in S-bend optical waveguide

A new theoretical version of loss calculation in optical waveguides S-bend has been developed. We derived a simple quasi-analytic theory based on integration of a phenomenological absorption coefficient. The general aims are to find simple methods of predicting the loss in bends whose functional form is described by a dasiashape functionpsila y = f(x), where f is continuous in its first derivative. The function we shall consider in detail is that describing a sinusoidal S-shaped bend. In the process, a number of significant anomalies in previously published formulations of bend loss are highlighted and resolved.