Elaboration of Optical Waveguides with an Accurate Control of the Refraction Index Profile

Glass is a good material for integrated optics, since the value and the gradient of its refractive index can be of the same order as in optical fibers, allowing an efficient coupling. The refractive index can be varied by exchanging the Na+ ions of glass with other ions (Ag+, K+, Li+...). This exchange can be spontaneous or electrically controlled ; the shape of the refractive index profile can be adjusted by varying the Electric field during the process. Thin (¿m) monomode or thick (200 ¿m) highly multimode planar waveguides can readily be obtained. Masking techniques can be used for elaborating 3 dimentional optical waveguides.