TE-TM mode converter

摘要

The converter has a substrate body (1) of lithium niobate with a monomode optical waveguide (3) formed by titanium diffusion extending along the substrate surface between two end surfaces (4,5). An input end of the waveguide is subjected to light from a source and carries an electroacoustic transducer (7) which generates acoustic surface waves collinear with the waveguide's longitudinal axis. A second monomode optical waveguide (6) extending along the substrate surface is made by proton exchange. The electroacoustic transducer covers both waveguides. The second waveguide is parallel to the first at least in a region associated with the transducer and separated from it by a distance so that at least partial coupling of the mode in the first waveguide to the second occurs for a stimulated surface wave of a selected conversion frequency.