Influence of a dielectric buffer layer on the field distribution in an electrooptic guided-wave device

An analytical solution to the field distribution for coplanar electrodes incorporating a buffer layer is obtained by using the method of images. The accuracy of the present analysis is found to be comparable to that obtained from a numerical solution, the finite element technique, The solution is applied to practical integrated optical devices incorporating waveguides with stripe geometry in order to directly estimate the overlap integral between optical and electric fields.