Optical integrated circuit for bidirectional communications and method for producing the same

摘要

The invention relates to an optical integrated circuit for bidirectional communications which is able to achieve a downsizing and high integration with the production cost thereof decreased. An optical waveguide circuit 20 is formed on a substrate 25 and a photo diode (PD) 8 is connected to the outgoing end 29 side thereof. The optical waveguide circuit 20 has a circuit of an optical wavelength division multiplexer which causes communication signal light ( lambda 1) inputted from a bidirectional light input/output port 33 to be transmitted through a communication light selective transmission filter 24 and to be outputted from a communication light output port 34 and causes non-communication light ( lambda 2) to be reflected by the communication light selective transmission filter 24 and to outgo through a non-communication light output port 35. A piezoelectric element 15 is provided on the upper part at the outgoing side 29 of the communication light output port 34. When the communication signal light passing through the optical waveguide circuit 20 is inputted into the PD 8, the PD 8 is actuated in the reception mode to receive communication signal light and is not driven in the transmission mode to reflect communication signal light toward the optical waveguide circuit 20 side by a high reflection coating film 30. The reflection light is given polarization plane modulation by the piezoelectric element 15, and the polarization plane modulated light is transmitted from the bidirectional light input/output port 33.