Propagation characteristics and losses in graded tapered slab optimal coupler

An analysis of a graded tapered glass waveguide is presented. A technique for constructing the waveguide is described. An applied electric field is varied along the length of the waveguide while the temperature is raised. As a result, the extent of diffusion of silver ion in the glass is larger at high electric field regions. This method should produce a graded index tapered slab waveguide whose depth varies along the length of the waveguide. Simple relations for angular dispersion and losses for such a coupler are presented