Tapered-channel ferrules and optical fiber connectors employing same
Ferrules having at least one tapered fiber channel that supports at least one optical fiber are disclosed. The at least one tapered fiber channel is defined by at least one channel wall. The material making up the channel wall is at least one of deformable and removable by forcible contact by the at least one optical fiber when the optical fiber is inserted into the fiber channel. This results in the formation of an interference fit between the front channel end and the optical fiber end when the diameter of the optical fiber end exceeds the diameter of the channel front end. The fiber channel wall may optionally include at least one deformable and/or removable-by-contact protrusion, with the at least one protrusion preferably being located in the channel section adjacent the narrow front channel end. Methods of forming the ferrules are also disclosed. Single-fiber and multi-fiber optical fiber connectors that employ the ferrules are also disclosed.
1. A method of forming a ferrule that supports at least one optical fiber having an end, comprising:
providing a ferrule mold having a cavity;
inserting at least one tapered pin within the cavity, wherein the tapered pin has an outside shape that corresponds to a desired tapered fiber channel;
adding a molding material to the mold cavity to cover the at least one tapered pin;
allowing the molding material to cure to form a ferrule body around the at least one tapered pin, wherein the ferrule body is at least one of deformable and removable by contact by the optical fiber;
removing the at least one tapered pin from the cured molding material to form at least one tapered channel having a smaller front end and a larger back end, wherein the at least one fiber channel includes a wall;
inserting at least one optical fiber with an end into the respective at least one ferrule channel at the backend, wherein the optical fiber end has an outer edge and has a diameter larger than the fiber channel front end; and
removing material from the fiber channel wall with the optical fiber edge to form an interference fit between the optical fiber end and the fiber channel front end.
2. The method of claim 1 , further comprising:
arranging a plurality of tapered pins within the cavity; and
removing the array of tapered pins from the cured molding material to form a plurality of tapered channels.
3. The method of claim 1 , further comprising:
providing the at least one tapered pin with at least one indent so that the at least one tapered channel has at least one protrusion that is also at least one of deformable and removable by contact by the optical fiber.
4. The method of claim 3 , wherein the at least one indent is formed in an end section of the at least one tapered pin, wherein the end section is untapered.
5. The method of claim 1 , wherein the at least one fiber channel includes a wall, and further comprising:
inserting at least one optical fiber with an end into the respective at least one ferrule channel at the back end, wherein the optical fiber end is larger than the fiber channel front end; and
deforming the fiber channel wall with the optical fiber to form an interference fit between the optical fiber end and the fiber channel front end.
6. The method of claim 5 , wherein the channel front end has a diameter D 34 , the fiber end has a diameter D 54 , wherein ΔD(%)=100*(D 54 −D 34 )/D 54 is in the range 0≦ΔD(%)≦1%.
7. The method of claim 1 , wherein the channel front end has a diameter D 34 , the fiber end has a diameter D 54 , wherein ΔD(%)=100*(D 54 −D 34 )/D 54 is in the range 0≦ΔD(%)≦1%.
8. The method of claim 1 , including forming the molding material from at least one of a thermoplastic material and thermoset material.