OPTICAL CONNECTION OF OPTICAL FIBERS TO GRATING COUPLERS
To couple light between an optical fiber and a grating coupler of a photonic integrated circuits, a mirror is provided to turn light to/from the optical fiber to allow the axis of the optical fiber to be oriented at small angles or parallel to the surface of the PIC, and lowered close to the surface of the PIC. The mirror is further configured to reshape light from a flat polished optical fiber to produce a mode field resembling the mode field of an angled polished optical fiber, to match the design angle of existing grating couplers that are designed to work with angled polished optical fibers. The mirror and optical fiber alignment structure in the optical connector are integrally/simultaneous formed by precision stamping.
1 . An optical coupling between an optical fiber and a grating coupler of a photonic integrated circuit (PIC), comprising:
a stamped optical bench comprising a stamped structured reflective surface, wherein the stamped optical bench supports an optical fiber in optical alignment with respect to the structured reflective surface, wherein the structured reflective surface turns light transmitted between the grating coupler and the optical fiber, and wherein the structured reflective surface includes a reflective surface profile that is structured to reshape light to produce a mode field that matches the optical fiber input/output and the design angle of the grating coupler.
2 . The optical coupling as in claim 1 , wherein the optical fiber is a flat polished optical fiber, and wherein the structured reflective surface is configured to reshape light input/output of the flat polished optical fiber, to produce a mode field resembling the mode field of an angled polished optical fiber, so as to match the design angle of existing grating couplers that are designed to work with angled polished optical fibers.
3 . The optical coupling as in claim 2 , wherein the optical bench further comprising a fiber alignment feature for aligning the optical fiber to the structured reflective surface and wherein the structured reflective surface and the optical fiber alignment structure are integrally/simultaneous formed by precision stamping, which allows them to be produced economically in high or small volumes, while improving tolerance, manufacturability, ease of use, functionality and reliability.
4 . A method of optically coupling an optical fiber to a grating coupler of a photonic integrated circuit (PIC), comprising:
providing a stamped optical bench comprising a stamped structured reflective surface, wherein the stamped optical bench supports an optical fiber in optical alignment with respect to the structured reflective surface, wherein the structured reflective surface turns light transmitted between the grating coupler and the optical fiber, and wherein the structured reflective surface includes a reflective surface profile that is structured to reshape light to produce a mode field that matches the optical fiber input/output and the design angle of the grating coupler.
5 . The method as in claim 4 , wherein the optical fiber is a flat polished optical fiber, and wherein the structured reflective surface is configured to reshape light input/output of the flat polished optical fiber, to produce a mode field resembling the mode field of an angled polished optical fiber, so as to match the design angle of existing grating couplers that are designed to work with angled polished optical fibers.
6 . The method as in claim 5 , wherein the optical bench further comprising a fiber alignment feature for aligning the optical fiber to the structured reflective surface and wherein the structured reflective surface and the optical fiber alignment structure are integrally/simultaneous formed by precision stamping, which allows them to be produced economically in high or small volumes, while improving tolerance, manufacturability, ease of use, functionality and reliability.