Patent ID: 7877016
Filing Date: 2011-01-25
Classification: H04B,H04J

Abstract:
1. A photonic integrated circuit, comprising: a substrate; a plurality of semiconductor layers provided on the substrate; a waveguide provided on the substrate; an input/output port; an optical coupler having first, second, and third ports, the coupler including a first portion of one of the plurality of semiconductor layers, the waveguide being coupled to the input/output port and the first port of the optical coupler; a laser diode that provides an outgoing signal at a first wavelength to the second port of the coupler; and a photodiode coupled to the third port of the optical coupler, said one of the plurality of semiconductor layers extending continuously from the first portion into the photodiode, such that the photodiode includes a second portion of said one of the plurality of semiconductor layers, wherein the optical coupler has a coupling length and a splitting ratio such that a substantial portion of an incoming signal at a second wavelength is directed to said third port of the optical coupler and passed to the photodiode, and a substantial portion of the outgoing signal is directed to the first port of the optical coupler and passed to the input/output port.