Multi-fiber interface apparatus for photonic integrated circuit

Abstract

Multi-fiber interface apparatuses providing a double reflection expanded beam arrangement include one or more substrates being configured to mountably receive a photonic integrated circuit (PIC), a fiber array coupling member mounted to a substrate, optical elements associated with the substrate and/or the fiber array coupling member, and one or more additional features. An additional feature according to certain implementations includes one or more passive substrate alignment features for aligning substrates to promote optical coupling between optical fibers and the PIC. In certain implementations configured for interfacing with printed circuit boards (PCBs), an additional feature includes a recess defined in an optically transmissive substrate in which a PIC is mounted, or includes a recess defined in a PCB into which the PIC is mounted. Various embodiments provide relaxed fiber alignment tolerances with simplified fabrication and system integration capabilities.

What is claimed is: 
     
         1 . A multi-fiber interface apparatus for a photonic integrated circuit (PIC), the multi-fiber interface apparatus comprising:
 an optically transmissive substrate having a first face and an opposing second face, the optically transmissive substrate defining a recess configured to receive a PIC, with the PIC being mountable to the optically transmissive substrate; and   a fiber array coupling member mounted to the optically transmissive substrate and configured to receive a plurality of optical fibers, the fiber array coupling member comprising (i) a plurality of optical beam turning elements and (ii) a plurality of second mirrors, configured to promote optical coupling between the plurality of optical fibers and the PIC when the PIC is mounted to the optically transmissive substrate.   
     
     
         2 . The multi-fiber interface apparatus of  claim 1 , further comprising a plurality of second focusing lenses arranged in an optical path between the plurality of second mirrors and the PIC. 
     
     
         3 . The multi-fiber interface apparatus of  claim 1 , further comprising a plurality of first mirrors configured to reflect beams received from the plurality of optical beam turning elements toward the plurality of second mirrors. 
     
     
         4 . The multi-fiber interface apparatus of  claim 3 , further comprising a plurality of first focusing lenses arranged in an optical path between the plurality of first mirrors and the plurality of second mirrors. 
     
     
         5 . The multi-fiber interface apparatus of  claim 1 , wherein:
 the recess is defined through the first face and through less than an entire thickness of the optically transmissive substrate;   the fiber array coupling member is mounted to or along the second face of the optically transmissive substrate; and   the optically transmissive substrate is configured to be received by a printed circuit board with the PIC being arrangeable in the recess between the substrate and the printed circuit board.   
     
     
         6 . The multi-fiber interface apparatus of  claim 1 , wherein the optically transmissive substrate comprises a plurality of electrically conductive vias extending through at least a portion of a thickness of the optically transmissive substrate. 
     
     
         7 . The multi-fiber interface apparatus of  claim 1 , further comprising at least one passive alignment feature configured to align the PIC with the optically transmissive substrate to promote optical coupling between the plurality of optical fibers and the PIC when the PIC is mounted to the optically transmissive substrate. 
     
     
         8 . The multi-fiber interface apparatus of  claim 1 , wherein the plurality of optical beam turning elements comprises a plurality of beam turning mirrors. 
     
     
         9 . The multi-fiber interface apparatus of  claim 1 , wherein the plurality of optical beam turning elements comprises beveled ends of the plurality of optical fibers when the plurality of optical fibers are received by the fiber array coupling member. 
     
     
         10 . The multi-fiber interface apparatus of  claim 1 , wherein the optically transmissive substrate comprises a first substrate portion defining the first face and a second substrate portion defining the second face, wherein the first substrate portion and the second substrate portion are joined to one another along a surface arranged between the first face and the second face. 
     
     
         11 . A multi-fiber interface apparatus for a photonic integrated circuit (PIC), the multi-fiber interface apparatus comprising:
 a printed circuit board defining a recess;   an optically transmissive substrate having a first face and an opposing second face, the optically transmissive substrate being mounted along the first face to the printed circuit board;   a PIC mounted to the optically transmissive substrate and arranged within the recess; and   a fiber array coupling member mounted to the optically transmissive substrate along the second face and configured to receive a plurality of optical fibers, the fiber array coupling member comprising (i) a plurality of optical beam turning elements and (ii) a plurality of second mirrors, configured to promote optical coupling between the plurality of optical fibers and the PIC.   
     
     
         12 . The multi-fiber interface apparatus of  claim 11 , further comprising a plurality of second focusing lenses arranged in an optical path between the plurality of second mirrors and the PIC. 
     
     
         13 . The multi-fiber interface apparatus of  claim 11 , further comprising a plurality of first mirrors configured to reflect beams received from the plurality of optical beam turning elements toward the plurality of second mirrors. 
     
     
         14 . The multi-fiber interface apparatus of  claim 13 , further comprising a plurality of first focusing lenses arranged in an optical path between the plurality of first mirrors and the plurality of second mirrors. 
     
     
         15 . The multi-fiber interface apparatus of  claim 11 , wherein the optically transmissive substrate comprises a plurality of electrically conductive vias extending through at least a portion of a thickness of the optically transmissive substrate. 
     
     
         16 . The multi-fiber interface apparatus of  claim 11 , further comprising at least one passive alignment feature configured to align the PIC with the optically transmissive substrate to promote optical coupling between the plurality of optical fibers and the PIC. 
     
     
         17 . The multi-fiber interface apparatus of  claim 11 , wherein the plurality of optical beam turning elements comprises a plurality of beam turning mirrors. 
     
     
         18 . The multi-fiber interface apparatus of  claim 11 , wherein the plurality of optical beam turning elements comprises beveled ends of the plurality of optical fibers when the plurality of optical fibers are received by the fiber array coupling member. 
     
     
         19 . The multi-fiber interface apparatus of  claim 11 , wherein the optically transmissive substrate comprises a first substrate portion defining the first face and a second substrate portion defining the second face, wherein the first substrate portion and the second substrate portion are joined to one another along a surface arranged between the first face and the second face.