Methods and apparatuses for bonding in athermal optical fiber packages

Abstract

An athermal package for fiber photonic devices includes a ferrule to attach the optical fiber to the package. The ferrule has an opening to receive the optical fiber. The ferule is collapsed to attach the optical fiber to the athermal package. Alternatively, the athermal package uses adhesive bonds disposed in pockets of the package. The pockets have a narrow end and a wide end, with the narrow ends facing each other. The adhesive bonds are disposed in the pockets in contact the narrow ends of the pockets but not with the wide ends. The narrow ends physically confine the adhesive bonds so that if the bonds expand or contract due to environmental conditions (or the curing process), the adhesive either expands or contracts near the wide ends of the pockets. This allows the strain on the optical fiber segment between the bonds to remain substantially constant.

1 . An apparatus, comprising: 
 a package attachable to an optical fiber segment that includes a photonic device between first and second points on the optical fiber segment, the package having: 
 a first ferrule fixedly attachable to the first point of the optical fiber segment; and  
 a second ferrule fixedly attachable to the second point of the optical fiber segment.  
   
   
   
       2 . The apparatus of  claim 1  wherein the package further comprises first, second and third portions, the third portion connected to the first and second portions, and the first and second ferrules are fixedly attached to first and second portions.  
   
   
       3 . The apparatus of  claim 2  wherein the third portion has an adjustable length.  
   
   
       4 . The apparatus of  claim 2  wherein the third portion comprises a material that is different from materials of the first and second portions, the materials of the first, second and third portions selected to compensate for size changes caused by a change in temperature.  
   
   
       5 . The apparatus of  claim 2  wherein the photonic device comprises a fiber Bragg grating (FBG).  
   
   
       6 . The apparatus of  claim 2  wherein the first and second portions respectively include first and second recesses, the first and second ferrules being respectively disposed in the first and second recesses.  
   
   
       7 . The apparatus of  claim 2  wherein the first and second portions respectively include first and second raised portions, the first and second ferrules respectively contacting the first and second raised portions.  
   
   
       8 . The apparatus of  claim 7  wherein the first and second raised portions include an opening to pass the optical fiber segment.  
   
   
       9 . The apparatus of  claim 6  wherein the first and second portions respectively include first and second openings to pass the optical fiber segment.  
   
   
       10 . The apparatus of  claim 3  wherein the length of the third portion is adjustable to achieve a selected strain on the optical fiber segment when attached to the package.  
   
   
       11 . The apparatus of  claim 1  wherein the first and second ferrules are collapsed to attach the optical fiber segment to the package.  
   
   
       12 . A method, comprising 
 fitting a first ferrule to a first point an optical fiber, the optical fiber including a photonic device between the first point and a second point on the optical fiber;    collapsing the first ferrule to fixedly attach the first ferrule to the optical fiber;    fitting a second ferrule to the second point on the optical fiber;    collapsing the second ferrule to fixedly attach the second ferrule to the optical fiber; and    attaching the first and second ferrules to an athermal package.    
   
   
       13 . The method of  claim 12  wherein the package further comprises first, second and third portions, the third portion connected to the first and second portions, and the first and second ferrules are fixedly attached to first and second portions.  
   
   
       14 . The method of  claim 12  further comprising adjusting a length of the third portion to adjust a strain on the optical fiber.  
   
   
       15 . The method of  claim 12  wherein the photonic device comprises a fiber Bragg grating (FBG).  
   
   
       16 . The method of  claim 12  wherein attaching the first and second ferrules to the athermal package comprises disposing the first and second ferrules into first and second recesses in the athermal package.  
   
   
       17 . A system, comprising: 
 an optical signal source;    an optical fiber coupled to the optical signal source; and    a photonic device coupled to the optical fiber, wherein the photonic device is implemented between first and second points of a segment of optical fiber, the photonic device including a package attached to the optical fiber segment between the first and second points, the package having:    a package attachable to an optical fiber segment that includes a photonic device between first and second points on the optical fiber segment, the package having: 
 a first ferrule fixedly attachable to the first point of the optical fiber segment; and  
 a second ferrule fixedly attachable to the second point of the optical fiber segment.  
   
   
   
       18 . The system of  claim 17  wherein the first and second ferrules are collapsed to attach the optical fiber segment to the package.  
   
   
       19 . The system of  claim 17  wherein the package further comprises first, second and third portions, the third portion connected to the first and second portions, and the first and second ferrules are fixedly attached to first and second portions.  
   
   
       20 . The system of  claim 17  wherein the photonic device comprises a fiber Bragg grating (FBG).  
   
   
       21 . The system of  claim 19  wherein the first and second portions respectively include first and second recesses, the first and second ferrules being respectively disposed in the first and second recesses.  
   
   
       22 . The system of  claim 19  wherein the first and second portions respectively include first and second raised portions, the first and second ferrules respectively contacting the first and second raised portions.  
   
   
       23 . The system of  claim 19  wherein the third portion has an adjustable length.