Method and system for fabricating an optical fiber device for shape sensing

Abstract

There is described a method of fabricating an optical fiber device, the method comprising: positioning longitudinal portions of a plurality of optical fibers alongside each other in a given geometrical relationship, depositing liquid coating material around the longitudinal portions of the plurality of optical fibers; and the liquid coating material setting up around the longitudinal portions of the plurality of optical fibers thereby maintaining said given geometrical relationship along the longitudinal portions.

What is claimed is: 
     
         1 . A method of fabricating an optical fiber device, the method comprising: positioning longitudinal portions of a plurality of optical fibers alongside each other in a given geometrical relationship, depositing liquid coating material around the longitudinal portions of the plurality of optical fibers; and the liquid coating material setting up around the longitudinal portions of the plurality of optical fibers thereby maintaining said given geometrical relationship along the longitudinal portions. 
     
     
         2 . The method of  claim 1  wherein said depositing includes extruding the liquid coating material around the longitudinal portions of the plurality of optical fibers while maintaining said given geometrical relationship. 
     
     
         3 . The method of  claim 2  wherein said extruding includes forcing the liquid coating material at a longitudinal position around the longitudinal portions of the plurality of optical fibers and moving the longitudinal portions of the plurality of optical fibers longitudinally during said forcing. 
     
     
         4 . The method of  claim 3  wherein said moving includes longitudinally pulling on ends of the plurality of optical fibers. 
     
     
         5 . The method of  claim 3  wherein said moving is performed as the longitudinal portions of the plurality of optical fibers are longitudinally received in an opening having an inner surface confining the plurality of optical fibers into the given geometrical relationship. 
     
     
         6 . The method of  claim 5  wherein the inner surface of the opening has a dimension below 1 mm, preferably below 500 μm and more preferably below 400 μm. 
     
     
         7 . The method of  claim 1  wherein said depositing includes maintaining the plurality of optical fibers parallel to one another. 
     
     
         8 . The method of  claim 1  wherein said depositing includes melting coating material thereby forming the liquid coating material, and wherein said setting up includes cooling the liquid coating material. 
     
     
         9 . The method of  claim 1  further comprising, prior to said depositing, heating a plurality of optical fiber preforms, and drawing the plurality of optical fiber preform into the plurality of optical fibers. 
     
     
         10 . The method of  claim 9  further comprising, after said drawing, inscribing one or more optical gratings along a portion of each of the plurality of optical fibers. 
     
     
         11 . The method of  claim 10  wherein at least one of the optical gratings has a random continuous distribution such that a return signal propagating in said optical fiber has a full width at half maximum bandwidth ranging between about 0.1 THz and about 40 THz. 
     
     
         12 . The method of  claim 1  wherein said positioning include positioning at least an additional component relative to the plurality of optical fibers, said depositing including depositing liquid coating material also around said additional component, the liquid coating material setting up around the additional component as well.