OPTICAL MULTIPLEXER/DEMULTIPLEXER

摘要

PURPOSE:To provide an optical multiplexer/demultiplexer with a light frequency selecting function and a transmission band width varying function and to expand the application range of the optical multiplexer/demultiplexer by inserting optical phase controllers into plural channel waveguides corresponding to their lengths. CONSTITUTION:An input waveguide 2, slave waveguides 3 and 5, a channel waveguide 4, and an output waveguide 6 are connected on a substrate 1. The channel waveguides 4 consists of plural waveguides which have the same curvature and differ in length and the length of the waveguide is made long to increase resolution even with narrow frequency intervals. Further, the channel waveguide 4 is loaded with a thermooptical phase shifter 7 as a phase controller formed corresponding to the length of each waveguide. This thermooptical phase shifter 7 is a thin-film heater and the refractive index is varied by varying the temperature to shift a light frequency. The thermooptic phase shifter 7 is made to correspond to the length of the channel waveguide 4 so as to make frequency shifts equally among the respective channel waveguides.