Coupler assembly for an optical backplane system

Abstract

A coupler assembly for an optical backplane system having a backplane and two or more circuit packs connected to that backplane. Each circuit pack has an optical transceiver and the backplane has an optical pipe (e.g., an array of waveguides) adapted to guide optical signals between the transceivers of different circuit packs. A coupler assembly is provided for each transceiver to couple light between that transceiver and the optical pipe. Advantageously, the coupler assembly has a movable optical element that can accommodate possible misalignment between the backplane and the circuit pack. In one embodiment, the movable optical element is an array of MEMS mirrors, each mirror adapted to direct light between an optical transmitter or receiver and the corresponding waveguide of the optical pipe.

1 . A coupler assembly adapted to provide optical coupling between an optical transceiver of a circuit pack and an optical pipe of a backplane, the coupler assembly comprising a mirror adapted to move with respect to a base of the coupler assembly and to direct light between the optical transceiver and the optical pipe, whereby said optical coupling is enabled.  
   
   
       2 . The coupler assembly of  claim 1 , wherein, if there is a misalignment between the backplane and the circuit pack, the coupler assembly is adapted to substantially compensate the effect of said misalignment on said optical coupling using said movement of said mirror.  
   
   
       3 . The coupler assembly of  claim 1 , wherein said mirror is part of a MEMS device attached to the base of the coupler assembly.  
   
   
       4 . The coupler assembly of  claim 3 , wherein the coupler assembly is adapted to receive electrical power for the MEMS device from the circuit pack.  
   
   
       5 . The coupler assembly of  claim 1 , wherein the coupler assembly is adapted to move the mirror in response to changes in relative orientation of the backplane and the circuit pack to maintain said optical coupling.  
   
   
       6 . The coupler assembly of  claim 1 , wherein: 
 the optical transceiver is adapted to process two or more optical signals; and    the coupler assembly comprises said mirror and at least one other mirror, each of said mirrors being adapted to move with respect to the base and to direct a respective optical signal between the optical pipe and the optical transceiver, wherein the coupler assembly is adapted to provide optical coupling for each of the two or more optical signals.    
   
   
       7 . The coupler assembly of  claim 6 , wherein the coupler assembly is adapted to adjust orientation of each of said mirrors to automatically track changes in relative orientation of the backplane and the circuit pack to maintain the optical coupling for each of the two or more optical signals.  
   
   
       8 . The coupler assembly of  claim 6 , further comprising a first plurality of waveguides, each waveguide of said first plurality adapted to be optically coupled to the optical transceiver, wherein: 
 the optical pipe comprises a second plurality of waveguides; and    each of said movable mirrors is adapted to direct the respective optical signal between a waveguide of the first plurality and a waveguide of the second plurality to provide optical coupling for said respective optical signal.    
   
   
       9 . The coupler assembly of  claim 1 , further comprising an optical waveguide adapted to be optically coupled to the optical transceiver, wherein the mirror is adapted to direct an optical signal between the optical waveguide and the optical pipe.  
   
   
       10 . The coupler assembly of  claim 1 , wherein: 
 the optical pipe comprises a first optical waveguide;    the mirror is adapted to direct an optical signal between the optical transceiver and the first optical waveguide; and    the coupler assembly comprises a second optical waveguide adapted to be optically coupled to the optical transceiver, wherein the mirror is adapted to direct the optical signal between the first and second optical waveguides.    
   
   
       11 . A circuit pack adapted to be coupled to a backplane, said backplane having an optical pipe adapted to transmit optical signals through the backplane, said circuit pack comprising: 
 a coupler adapted to optically couple (i) an optical transceiver of the circuit pack and (ii) the optical pipe, said coupler comprising a mirror adapted to move with respect to a base of the coupler and to direct light between the optical transceiver and the optical pipe, whereby optical coupling between the optical transceiver and the optical pipe is enabled.    
   
   
       12 . The circuit pack of  claim 11 , wherein, if there is a misalignment between the backplane and the circuit pack, the coupler is adapted to substantially compensate the effect of said misalignment on said optical coupling using said movement of said mirror.  
   
   
       13 . The circuit pack of  claim 11 , wherein said mirror is part of a MEMS device attached to the base of the coupler.  
   
   
       14 . The circuit pack of  claim 11 , wherein the coupler is adapted to move the mirror in response to changes in relative orientation of the backplane and the circuit pack to maintain said optical coupling.  
   
   
       15 . The circuit pack of  claim 11 , wherein: 
 the optical transceiver is adapted to process two or more optical signals; and    the coupler comprises said mirror and at least one other mirror, each of said mirrors being adapted to move with respect to the base and to direct a respective optical signal between the optical pipe and the optical transceiver, wherein the coupler is adapted to provide optical coupling for each of the two or more optical signals.    
   
   
       16 . The circuit pack of  claim 15 , wherein the coupler is adapted to adjust orientation of each of said mirrors to automatically track changes in relative orientation of the backplane and the circuit pack to maintain the optical coupling for each of the two or more optical signals.  
   
   
       17 . The circuit pack of  claim 15 , wherein: 
 the coupler comprises a first plurality of waveguides, each waveguide of said first plurality adapted to be optically coupled to the optical transceiver;    the optical pipe comprises a second plurality of waveguides; and    each of said movable mirrors is adapted to direct the respective optical signal between a waveguide of the first plurality and a waveguide of the second plurality to provide optical coupling for said respective optical signal.    
   
   
       18 . The circuit pack of  claim 11 , wherein the coupler comprises an optical waveguide adapted to be optically coupled to the optical transceiver, wherein the mirror is adapted to direct an optical signal between the optical waveguide and the optical pipe.  
   
   
       19 . The circuit pack of  claim 11 , wherein: 
 the optical pipe comprises a first optical waveguide;    the mirror is adapted to direct an optical signal between the optical transceiver and the first optical waveguide; and    the coupler comprises a second optical waveguide adapted to be optically coupled to the optical transceiver, wherein the mirror is adapted to direct the optical signal between the first and second optical waveguides.    
   
   
       20 . A method of optically coupling an optical transceiver of a circuit pack and an optical pipe of a backplane, the method comprising: 
 moving a mirror with respect to at least one of the circuit pack and the backplane to direct light between the optical transceiver and the optical pipe and to automatically track changes in relative orientation of the backplane and the circuit pack, whereby said optical coupling is enabled.