US Patent 10488596 Optical fiber mounted photonic integrated circuit device

The invention relates to an optical fiber mounted photonic integrated circuit device, wherein the tolerance for positioning in terms of the coupling between the single mode optical fibers and the optical waveguides provided on the photonic integrated circuit device is increased. An optical waveguide core group is provided in such a manner where a plurality of optical waveguide cores having a portion that is tapered in the direction of the width within a plane are aligned parallel to each other at intervals that allow for mutual directional coupling and that are narrower than the width of the core of the single mode optical fiber, and the inclined connection end surface of the single mode optical fiber and the upper surface of an end portion of the optical waveguide cores face each other for coupling.