| 摘要 |
PURPOSE:To provide the optical function element with which a large change in reflectivity or transmittance is obtainable by providing light reflecting means which are respectively different in reflectivity at the output ends of two light guides and executing the switching of an optical switch by a control means from the outside. CONSTITUTION:A directional coupler type parallel waveguide part 10 is formed in the central part of the two light guides 2, 3. The reflecting means 4 of the high reflectivity is provided at the output end 21 of the light guide 2 and the reflecting means 5 consisting of a non-reflection film is provided at the output end 31 of the light guide 3. Pulse voltages are impressed between the metallic electrode film on the light guide 2 or 3 and the metallic electrode film on the rear surface of a substrate 1 by using a control power source 6'. Incident light Pi switches to the light guide 3 when the impressed voltage is 0. The light is switched to the light guide 2 by the impressed voltage V0. There is substantially no reflection at the output end 31 of the light guide 3 and the light is fully reflected at the output end 21 of the light guide 2. The arbitrary control of the reflectivity (Pr/Pi) at the input end and the transmittance (Pt/Pi) at the output end by the external electric field is, therefore, possible. |
