Measurement of Two Dimensional Refractive Index Profiles of Channel Waveguides using an Interferometric Technique

Two dimensional refractive index profiles of ion exchanges channel waveguides in glass have been measured using an interferometric method. In order to obtain depth data, a shallow bevel is produced in the glass by polishing. A regularization algorithms for the extraction of the phase data from the interferometer image is presented. The method is applied to waveguides formed by the electric field assisted diffusion of Cu+ ions into a borosilicate glass. The index change obtained from the interferometer is in good agreement with that obtained from measurements on planar waveguides.