Optical integrated circuit

摘要

An optical integrated circuit includes a substrate and a thin film formed on the substrate. A waveguide is formed by the thin film. A grating coupler includes a plurality of coupling regions for introducing an incident light beam into the waveguide, and for separating the incident light beam into output light beams propagated in the waveguide in different directions respectively. The output light beams are in a same waveguide mode and have polarization directions perpendicular to each other respectively. Photodetectors are exposed to the output light beams propagated in the waveguide for detecting the output light beams respectively.