Freq independent feeding of opt. radiation into thin film waveguide - involves prismatic coupling element and optical waveguide

摘要

The waveguide is applied on a layer substrate and is separated from the coupling element by a slot, so that the total reflection from the coupling element face opposite to the waveguide is partly suppressed. The angle between the light entry face and the total reflecting face, and the waveguide thickness are such that phase velocities of the radiation in the coupling element and in the waveguide satisfy specified relations. The surface of the thin film waveguide may be curved, while the prism is an equilateral right angled triangle.