Optical dispersion curves of a light waveguide with a guiding region cross-section resembling a double convex lens

Abstract

This paper reports the study of the dispersion characteristics of a new light waveguide having a cross-sectional shape resembling that of a double convex lens. This shape may be considered as a distortion of elliptical shape. If the elliptical waveguide is given a transverse compression at the extremities of the major axis, the distortion may be represented by a double convex lens. Using Goell's point matching method under the weak guidance condition, the modal characteristic equation has been obtained. From the characteristic equation we get the dispersion curves for some low order modes. It is found that these curves are of the expected shapes and are crowded near the cut off V-values.