Optical fiber ferrule assembly and optical module and optical connector using the same

Abstract

In an optical fiber ferrule assembly, a bare optical fiber, an end coating of which is removed, is inserted and fixed into the central hole of a ferrule body. By setting the distance between a boundary point at which the bare optical fiber is fixed at the rear end of the ferrule body and a next point at which the bare optical fiber is fixed to a fixing member which is formed integrally with the ferrule body via a coating of an optical fiber core to the range of 0.5 to 6 mm, more preferably, to the range of 1 to 4 mm, stress concentration at the boundary point at which the bare optical fiber is bonded and the point at which the optical fiber core is fixed cab be reduced.

1 . An optical fiber ferrule assembly comprising: 
 an optical fiber ferrule body into which a bare optical fiber, the jacket of which is removed, is inserted and fixed into the central hole of the ferrule body with an adhesive; and    a fixing member, which is connected to the ferrule body and includes a core stop step to receive one end of the jacket, for fixing an inserted jacketed fiber connected to the bare optical fiber, the fixing member being bonded to the inserted jacketed fiber with the adhesive,    wherein the distance between a boundary point at which the bare optical fiber is inserted and fixed at the rear end of the central hole of the ferrule body and a boundary point at which the one end of the jacket is received covers a predetermined length.    
   
   
       2 . The optical fiber ferrule assembly according to  claim 1 , wherein the distance between the boundary point at which the bare optical fiber is inserted and fixed and the boundary point at which the one end of the jacket is received covers a length of 1 to 4 mm.  
   
   
       3 . The optical fiber ferrule assembly according to  claim 1 , wherein the fixing member for inserting and fixing the jacketed fiber is a tube-shaped fixing member.  
   
   
       4 . The optical fiber ferrule assembly according to  claim 1 , wherein the fixing member for inserting and fixing the jacketed fiber is a flanged fixing member.  
   
   
       5 . The optical fiber ferrule assembly according to  claim 1 , wherein the ferrule body is provided with a gap-adjusting hole having a diameter which is larger than the outside diameter of the bare optical fiber and which is smaller than the outside diameter of the jacketed fiber and having a length of 0.5 to 6 mm from the rear end to the front end thereof.  
   
   
       6 . An optical module, comprising the optical fiber ferrule assembly according to  claim 3 .  
   
   
       7 . An optical connector, comprising the optical fiber ferrule assembly according to  claim 4 .  
   
   
       8 . The optical module according to  claim 6 , wherein the ferrule body is provided with gap-adjusting hole having a diameter which is larger than the outside diameter of the bare optical fiber and which is smaller than the outside diameter of the jacketed fiber and having a length of 0.5 to 6 mm from the point at which the bare fiber enters the ferrule to the front boundary of the fiber jacket.  
   
   
       9 . The optical connector according to  claim 7 , wherein the ferrule body is provided with gap-adjusting hole having a diameter which is larger than the outside diameter of the bare optical fiber and which is smaller than the outside diameter of the jacketed fiber and having a length of 0.5 to 6 mm from the point at which bare fiber enters the ferrule to the front boundary of the fiber jacket.  
   
   
       10 . The optical fiber ferrule assembly according to  claim 3 , wherein the core stop step is in the central hole of the fixing member for stopping the insertion of the jacketed optical fiber at the predetermined depth.  
   
   
       11 . The optical fiber ferrule assembly according to  claim 10 , wherein the central hole of the fixing member has first and second different diameters.  
   
   
       12 . The optical fiber ferrule assembly according to  claim 11 , wherein the first diameter of the central hole of the fixing member is smaller than the diameter of the jacketed fiber and the second diameter is adapted to receive the jacketed fiber.  
   
   
       13 . The optical fiber ferrule assembly according to  claim 1 , wherein the bare optical fiber is fixed in the central hole of the ferrule by bonding with and adhesive.  
   
   
       14 . The optical fiber ferrule assembly according to  claim 13 , wherein the coated optical fiber is fixed to the fixing member by bonding with an adhesive.  
   
   
       15 . The optical ferrule assembly according to  claim 1 , wherein the coated optical fiber is fixed to the fixing member by bonding with an adhesive.  
   
   
       16 . The optical fiber ferrule assembly according to  claim 1 , wherein the distance between the boundary point at which the bare optical fiber is inserted and fixed and the boundary at which the one end of the jacket is received is a length of 2 to 4 mm and the ferrule has a drawing strength of at least 2 kgf.  
   
   
       17 . The optical fiber ferrule assembly according to  claim 1 , wherein the distance between the boundary point at which the bare optical fiber is inserted and fixed and the boundary point at which the one end of the jacket is received covers a length of 0.5 to 6 mm.