Bend-limited flexible optical interconnect device for signal distribution

Abstract

The invention relates to a bend limiting structure for preventing a flexible optical circuit from being bent too sharply. More particularly, the invention involves adding a bend limiting layer or layers to the flexible optical circuit and/or any housing or other structure within which it is enclosed or to which it is attached. The bend-limiting layer may comprise a plurality of blocks arranged in a line or plane and joined by a flexible film that is thinner than the blocks, with the blocks positioned close enough to each other so that, if that plane of blocks is bent a predetermined amount, the edges of the blocks will interfere with each other and prevent the plane from being bent any further. The blocks may be resilient also to provide a less abrupt bend-limiting stop.

What is claimed is: 
     
         1 . A device for interconnecting optical signals between at least one first optical component and at least one second optical component comprising:
 a flexible optical circuit substrate layer having first and second, opposed major surfaces;   a plurality of optical fibers disposed on the substrate, each of the optical fibers having a first end and a second end;   a bend limiting layer attached to the flexible optical circuit so as to bend with and substantially identically to the flexible optical circuit substrate, the bend limiting layer comprising a plurality of blocks disposed relative to each other such that adjacent pairs of the blocks contact each other when the bend limiting layer is bent a predetermined amount, thereby resisting further bending of the bend limiting layer and the flexible optical circuit substrate.   
     
     
         2 . The device of  claim 1 , wherein the bend limiting layer is attached to the first major surface of the flexible optical circuit substrate. 
     
     
         3 . The device of  claim 1  further comprising a housing within which the flexible optical circuit substrate is disposed, wherein the bend limiting layer is attached to the housing. 
     
     
         4 . The device of  claim 1  further comprising:
 at least a first light-guiding, fiber termination optical element disposed on the substrate adjacent the first ends of the optical fibers positioned to couple light with the optical fibers; and 
 at least a second light-guiding, fiber termination optical element disposed on the substrate adjacent the second ends of the optical fibers positioned to couple light with the optical fibers. 
 
     
     
         5 . The device of  claim 1 , wherein the light-guiding, fiber termination optical elements are lenses. 
     
     
         6 . The device of  claim 1 , wherein the flexible optical circuit substrate comprises a laminate having first and second layers, and wherein the plurality of optical fibers are embedded between the first and second layers. 
     
     
         7 . The device of  claim 1 , wherein the bend limiting layer further comprises a film interconnecting the blocks. 
     
     
         8 . The device of  claim 7 , wherein the film is resiliently stretchable. 
     
     
         9 . The device of  claim 7 , wherein the blocks and the film of the bend limiting layer are unitary. 
     
     
         10 . The device of  claim 7 , wherein the blocks extend in only one direction perpendicularly from a plane defined by the film. 
     
     
         11 . The device of  claim 1 , wherein the bend limiting layer comprises a first bend limiting layer disposed on the first major surface of the flexible optical circuit substrate and a second bend limiting layer disposed on the second major surface of the flexible optical circuit substrate. 
     
     
         12 . The device of  claim 1  wherein the blocks are arranged in a two dimensional planar array. 
     
     
         13 . The device of  claim 12  wherein the blocks are arranged in rows and columns. 
     
     
         14 . The device of  claim 12  wherein the bend limiting layer provides different bend limits in different orthogonal directions. 
     
     
         15 . The device of  claim 3  wherein the housing is flexible. 
     
     
         16 . The device of  claim 3  wherein the housing comprises first and second housing parts hingedly connected to each other.