Loss characteristics of circular hollow waveguides for incoherent infrared light

Abstract

A simple and convenient method was proposed for the calculation of transmission loss in a circular hollow waveguide. The method is based on a simple ray theory and is applicable to multimode transmission of incoherent light. In order to confirm the validity of the method, spectral losses of various kinds of hollow waveguide were measured and compared with the theoretical values. For a silica waveguide, good coincidence was obtained between calculated and measured values, whereas, for metallic waveguides, surface irregularities must be taken into account for prediction of optical losses.