Emission of surface light waves from a corrugated part of a thin-film waveguide

A theoretical analysis is made of the influence of interference on the emission of surface light waves from a corrugated part of a thin-film waveguide. It is shown that the interference effects are strongest when the film is corrugated on the substrate side. A strong dependence of the attenuation coefficient of a wave on the film thickness and its modulation period is confirmed experimentally. Recommendations are made on the efficient coupling of light into the film.