Optical circuit on printed circuit board

Abstract

Apparatus for packaging a fiber optic device along with electronic and opto-electronic components upon a printed circuit board. Bend members having arcuate shaped guide surfaces for directing fibers between various components are strategically mounted upon the top surface of the board. Passive fiber optic components are also mounted upon support means between bend members so that the fibers entering and exiting the passive component run tangent to the bend radius of the bend members. The radius of curvature of the bend members is within the bend tolerance of the fibers used in the device. The bend members and support members are formed of a material having a thermal coefficient of expansion that is about equal to that of the board material whereby thermally induced stresses on the board mounted components are minimized.

What is claimed is:  
     
       1. Apparatus for mounting fiber optic circuits upon a printed circuit board that includes 
       a printed circuit board containing both electrical and optical circuitry on the upper surfaces of said board,  
       bend members each containing an arcuate guide surface having a predetermined radius of curvature that is within the bend tolerance of optical fibers used in said optical circuitry,  
       mounting means for selectively attaching said bend members at predetermined spaced apart locations on the upper surface of the board,  
       support members attached to the upper surface of said board for mounting optical circuit components between spaced apart bend members,  
       a pair of spaced apart mandrels mounted upon the upper surface of said board about which spliced sections of said fiber optic circuitry are wound, each mandrel being formed by a plurality of circumferentially aligned bend members,  
       said bend members and said support members being formed of a material that has a thermal coefficient of expansion that is about equal to that of said optical fibers.  
     
     
       2. The apparatus of  claim 1  wherein said optical circuitry include coupler means for optically connecting active optical circuit components that are mounted on said board to said fiber optic circuit and run means on said board for electrically connecting the active component to an electrical header mounted on said board. 
     
     
       3. The apparatus of  claim 2  that further includes electrical circuit means mounted on said board for electrically supporting said active optical circuit components. 
     
     
       4. The apparatus of  claim 3  wherein at least one of said active components is a photodetector diode and the electrical support circuitry is mounted on said board in close proximity to said photodetector diode to enhance the operation of said diode. 
     
     
       5. The apparatus of  claim 1  wherein the thermal coefficient of expansion of said members and said optical fibers are about equal to that of the circuit board. 
     
     
       6. The apparatus of  claim 1  wherein said fiber optic circuit includes at least one wound fiber gain coil that is secured to the circuit board between two resilient discs. 
     
     
       7. The apparatus of  claim 1  wherein at least one of said support members further include a linear guide surface for directing the entering and exiting optical fibers of the passive component supported therein along a path that is tangential with the guide surfaces of the spaced apart bend members. 
     
     
       8. The apparatus of  claim 1  wherein said arcuate shaped guide surfaces of said bend members subtend an arc of about 90° or less. 
     
     
       9. Apparatus for mounting a fiber optic circuit upon a printed circuit board that includes 
       a printed circuit board,  
       bend members each containing an arcuate guide surface having a predetermined radius of curvature that is within the bend tolerance of optical fibers used in the optic circuit,  
       mounting means for selectively attaching the bend members at predetermined spaced apart locations on the upper surface of the board;  
       support members attached to the upper surface of said board for mounting passive optical circuit components between two spaced apart bend members, said bend members and said support members being formed of a material that has a thermal coefficient of expansion that is about equal to that of said board, wherein said optical circuits include coupler means for optically connecting active optical circuit components that are mounted on said board to said fiber optic circuit and run means on said board for electrically connecting the active component to an electrical header mounted on said board, and  
       a pump laser that is coupled to the fiber optic circuit and the electrical header.  
     
     
       10. The apparatus of  claim 9  wherein said board contains an opening that passes through said board, a heat sink mounted upon the lower surface of said board that spans said opening, and means for mounting said laser pump in said opening upon said heat sink. 
     
     
       11. The apparatus of  claim 10  wherein the heat sink contains a flat bottom surface that is parallel to the lower surface of said board, said bottom surface of the heat sink being a predetermined distance from the lower surface of said board whereby said bottom surface provides a mounting and locating surface for said board. 
     
     
       12. The apparatus of  claim 9  that includes stiffening means attached to said board for resisting both thermal and mechanically induced stresses. 
     
     
       13. The apparatus of  claim 9  that includes light input and light output terminals mounted on said board that are connected to said fiber optic circuit. 
     
     
       14. The apparatus of  claim 9  that further includes a base for supporting said board and a cover fitted to said base for enclosing said board. 
     
     
       15. Apparatus for mounting a fiber optic circuit upon a printed circuit board that includes 
       a printed circuit board,  
       bend members each containing an arcuate guide surface having a predetermined radius of curvature that is within the bend tolerance of optical fibers used in the optic circuit, wherein said arcuate shaped guide surfaces of said bend members subtend an arc of 90° or less,  
       mounting means for selectively attaching the bend members at predetermined spaced apart locations on the upper surface of the board.  
       support members attached to the upper surface of said board for mounting passive optical circuit components between two spaced apart bend members, said bend members and said support members being formed of a material that has a thermal coefficient of expansion that is about equal to that of said board, and  
       a pair of spaced apart mandrels mounted upon said board about which spliced sections of the fiber optic circuit are wound, each mandrel being formed by a plurality of circumferentially aligned bend members.  
     
     
       16. The apparatus of  claim 15  wherein a wound fiber gain coil is mounted inside at least one of said mandrels. 
     
     
       17. Apparatus for mounting fiber optic circuitry upon a printed circuit board that includes 
       a printed circuit board having a flat planar upper surface containing electrical circuitry thereon,  
       support members attached to the upper surface of the circuit board for mounting optical components containing optical fibers for carrying optical signals into and out of said components,  
       bend members mounted upon the upper surface of said board containing arcuate guide surfaces for physically engaging the optical fibers on the inside of each bend and directing said optical fibers toward and away from said optical components, each guide surface having a radius of curvature that is within the bend tolerance of the optical fibers, and  
       said bend members and said support members being formed of a material that has a thermal coefficient of expansion about equal to that of the optical fibers.  
     
     
       18. The apparatus of  claim 17  wherein the thermal coefficient of expansion of said board is about equal to that of the optical fibers. 
     
     
       19. The apparatus of  claim 17 , that further includes linear guides for further directing said optical fibers toward and away from said optical components along a path that is tangential to the arcuate guide surfaces on the bend members. 
     
     
       20. An opto- electronic device comprising:    
       
         a substrate containing both electrical and optical circuitry on the upper surface of the substrate;  
       
       
         an optical device attached to the upper surface of said substrate;  
       
       
         a plurality of optical fibers connected to said optical device;  
       
       
         a plurality of fiber guides attached to the upper surface of said substrate and disposed to direct said plurality of optical fibers, said plurality of fiber guides each having at least one arcuate guide surface;  
       
       
         a pair of spaced apart mandrels mounted upon the upper surface of said board about which spliced sections of said optical fibers are wound, each mandrel being formed by a plurality of circumferentially aligned fibers guides; and  
       
       
         an electronic device attached to the upper surface of said substrate.  
       
     
     
       21. The opto- electronic device of    claim 20    wherein said optical device comprises:    
       
         an input port;  
       
       
         an output port; and  
       
       
         a plurality of optical components disposed between said input port and said output port.  
       
     
     
       22. The opto- electronic device of    claim 21    further compromising:    
       
         a plurality of supports attached to the substrate for mounting the plurality of optical components thereto.  
       
     
     
       23. The opto- electronic device of    claim 22    wherein said plurality of optical components includes an optical gain block.    
     
     
       24. The opto- electronic device of    claim 23    further comprising:    
       
         two mandrels disposed to serve as guides for winding about a portion of said plurality of optical fibers; each of said mandrels having an arcuate guide surface, attached to the substrate;  
       
       
         a fiber gain coil; and  
       
       
         two discs positioned with said fiber gain coil therebetween.  
       
     
     
       25. The opto- electronic device of    claim 24    wherein the two discs are made of a resilient material.    
     
     
       26. The opto- electronic device of    claim 25    wherein a selected one of said plurality of supports comprises:    
       
         a linear fiber guide for directing at least two of said plurality of optical fibers to one of the at least one optical components.  
       
     
     
       27. The opto- electronic device of    claim 26    wherein the selected support is disposed longitudinally between two of said plurality of fiber guides, said linear fiber guide tangentially aligned with said arcuate guide surfaces of said two fiber guides.    
     
     
       28. The opto- electronic device of    claim 27    wherein the selected support contacts two of said plurality of fiber guides.    
     
     
       29. The opto- electronic device of    claim 28    wherein the substrate, the plurality of optical fibers, the plurality of fiber guides, and the plurality of supports have about the same coefficient of thermal expansion.    
     
     
       30. The opto- electrical device of    claim 22    wherein said plurality of optical components comprises:    
       
         at least one active optical component; and  
       
       
         at least one passive optical component operatively connected to said at least one active optical component.  
       
     
     
       31. The opto- electronic device of    claim 21    further comprising:    
         an integrated guide - support attached to the substrate for mounting of one of the plurality of optical components, said integrated guide - support including a center portion disposed between two arcuate guide surfaces.    
     
     
       32. The opto- electronic device of    claim 20    further comprising:    
       
         two mandrels disposed to serve as guides for winding a portion of said plurality of optical fibers.  
       
     
     
       33. The opto- electronic device of    claim 32    wherein each of the mandrels defines a curved guide surface.    
     
     
       34. The opto- electronic device of    claim 33    wherein said substrate is a printed circuit board having a first surface and a second surface.    
     
     
       35. The opto- electronic device of    claim 34    further comprising:    
       
         a heat sink mounted to the second surface of the printed circuit board, wherein the optical device includes a pump laser, and the pump laser is thermally coupled to said heat sink.  
       
     
     
       36. The opto- electronic device of    claim 35    wherein the optical device comprises:    
       
         an optical gain block mounted to the first surface of said printed circuit board, wherein the printed circuit board defines an opening, the pump laser extending through said opening in the printed circuit board for engagement with said optical gain block,  
       
       
         wherein the plurality of supports is mounted to the first surface of the printed circuit board.  
       
     
     
       37. The opto- electronic device of    claim 36    further comprising:    
       
         a stiffener attached to the printed circuit board.  
       
     
     
       38. The opto- electronic device of    claim 37    wherein the stiffener is disposed so as to moderate deflection of the printed circuit board due to thermally -  and mechanically - induced loading.    
     
     
       39. The opto- electronic device of    claim 36    further comprising:    
       
         a second substrate and  
       
       
         a cover attached to said second substrate forming a housing, wherein the printed circuit board is enclosed within said housing and is mounted to said second substrate.  
       
     
     
       40. The opto- electronic device of    claim 20    further comprising:    
       
         an electrical connector connected to the electronic device; and  
       
       
         a plurality of electrical leads connected to said electrical connector and the electronic device for transmitting electricity from said electrical connector to the electronic device.  
       
     
     
       41. The opto- electronic device of    claim 20    wherein the substrate is a printed circuit board.    
     
     
       42. The opto- electronic device of    claim 20    wherein the at least one arcuate guide surface is configured to position at least one of said plurality of optical fibers without adversely affecting the optical properties of said at least one optical fiber.    
     
     
       43. Apparatus for mounting fiber optic circuits that includes 
       
         a substrate containing both electrical and optical circuitry on the upper surface of the substrate,  
       
       
         bend members each containing an arcuate guide surface having a predetermined radius of curvature that is within the bend tolerance of optical fibers used in said optical circuitry, wherein said bend members are attached to the upper surface of said substrate,  
       
       
         support members attached to the upper surface of said substrate for mounting optical circuit components between spaced apart bend members, and  
       
       
         a pair of spaced apart mandrels mounted to the upper surface of said substrate about which spliced sections of said fiber optic circuitry are wound, each mandrel being formed by a plurality of circumferentially aligned bend members.  
       
     
     
       44. The apparatus of  claim 43  wherein said optical circuitry includes coupler means for optically connecting active optical circuit components that are attached to said substrate to said fiber optic circuit and said electrical circuitry including an electrical header mounted on said substrate electrically connected to the active optical circuit components.  
     
     
       45. The apparatus of  claim 44 , wherein said electrical circuitry attached to said substrate supports said active optical circuit components.  
     
     
       46. The apparatus of  claim 45  wherein at least one of said active optical circuit components is a photodetector diode, said electrical circuitry being mounted on said substrate in close proximity to said photodetector diode to enhance the operation of said photodetector diode.  
     
     
       47. The apparatus of  claim 43  wherein said bend members and said optical fibers have a thermal coefficient of expansion about equal to that of the substrate.  
     
     
       48. The apparatus of  claim 43  wherein said fiber optic circuit includes at least one fiber gain coil that is secured to the substrate between two resilient discs.  
     
     
       49. The apparatus of  claim 43  wherein at least one of said support members further include a linear guide surface for directing the entering and exiting optical fibers of a passive component supported therein.  
     
     
       50. The apparatus of  claim 43  wherein said arcuate shaped guide surfaces of said bend members subtend an arc of about  90 ° or less.  
     
     
       51. Apparatus for mounting a fiber optic circuit and electrical circuitry that includes 
       
         a substrate,  
       
       
         bend members each containing an arcuate guide surface having a predetermined radius of curvature that is within the bend tolerance of optical fibers used in the optic circuit, wherein said bend members are attached to said substrate,  
       
       
         support members attached to the substrate for mounting passive optical circuit components between two spaced apart bend members, wherein said optical circuit includes an optical coupler connecting active optical circuit components that are attached to said fiber optic circuit and said electrical circuitry including an electrical header mounted on said substrate electrically connected to the active optical circuit component, and  
       
       
         a pump laser that is coupled to the fiber optic circuit and the electrical header.  
       
     
     
       52. The apparatus of  claim 51  wherein said substrate contains an opening that passes through said substrate, a heat sink attached to said substrate on a surface opposite that to which the fiber optic circuit is attached and spanning said opening, wherein said laser pump is mounted in said opening upon said heat sink.  
     
     
       53. The apparatus of  claim 51  that includes a stiffener attached to said substrate for resisting both thermal and mechanically induced stresses.  
     
     
       54. The apparatus of  claim 51  that includes light input and light output terminals attached to said substrate that are connected to said fiber optic circuit.  
     
     
       55. The apparatus of  claim 51  that further includes a base for supporting said substrate and a cover fitted to said base for enclosing said substrate.  
     
     
       56. Apparatus for mounting a fiber optic circuit that includes 
       
         a substrate,  
       
       
         bend members each containing an arcuate guide surface having a predetermined radius of curvature that is within the bend tolerance of optical fibers used in the optic circuit, wherein said arcuate shaped guide surfaces of said bend members subtend an arc of  90 ° or less, wherein said bend members are attached to said substrate,  
       
       
         support members attached to said substrate for mounting passive optical circuit components between two spaced apart bend members, and  
       
       
         at least one mandrel attached to the substrate about which spliced sections of the fiber optic circuit are wound.  
       
     
     
       57. The apparatus of  claim 56  wherein a fiber gain coil is mounted to the at least one mandrel.  
     
     
       58. Apparatus for mounting fiber optic circuitry and electrical circuitry that includes 
       
         a substrate having a flat upper surface containing fiber optic circuitry and electrical circuitry thereon,  
       
       
         support members attached to the upper surface of said substrate for mounting optical components containing optical fibers for carrying optical signals into and out of said components,  
       
       
         bend member attached to said substrate and containing arcuate guide surfaces for physically engaging the optical fibers and directing said optical fibers toward and away from said optical components, each guide surface having a radius of curvature that is within the bend tolerance of the optical fibers, and  
       
       
         said bend members and said support members being formed of a material that has a thermal coefficient of expansion about equal to that of the optical fibers.  
       
     
     
       59. The apparatus of  claim 58  wherein said substrate has a thermal coefficient of expansion about equal to that of the optical fibers.  
     
     
       60. The apparatus of  claim 58 , that further includes linear guides for further directing said optical fibers toward and away from said optical components.