Coupler between optical fiber and optical waveguide, and photonic integrated circuit comprising same

A photonic integrated circuit comprising:

• a substrate;
• an optical waveguide disposed on the substrate;
• an optical fiber connected to the optical waveguide;
• and
• an optical fiber and optical waveguide coupler coupling the optical fiber to the optical waveguide,
• wherein the optical fiber and optical waveguide coupler includes
• an optical fiber coupling part disposed at an end of the optical fiber and having an inclined slanted cross-section,
• an optical waveguide coupling part corresponding to one part of the optical waveguide and in contact with the optical fiber coupling part, and
• a refractive index matching part covering the optical fiber coupling part and the optical waveguide coupling part and matching a refractive index between the optical fiber coupling part and the optical waveguide,
• the optical fiber coupling part exposes a core of the optical fiber, and
• a width of the one part of the optical waveguide coupling part gradually decreases along an extension direction of the optical waveguide.

A photonic integrated circuit comprising:

• a substrate;
• a plurality of optical waveguides disposed on the substrate;
• an optical fiber array including a plurality of optical fibers connected to the plurality of optical waveguides, respectively;
• a plurality of optical fiber and optical waveguide couplers coupling the optical fiber array to the plurality of optical waveguides;
• and
• an optical fiber fixing part fixing the optical fiber array onto the plurality of optical waveguides,
• wherein the optical fiber and optical waveguide coupler includes