Fiber optic connector element and method for its use

• US 4,964,688 A
• Filed: 07/27/1989
• Issued: 10/23/1990
• Est. Priority Date: 09/22/1988
• Status: Expired due to Term

• Current Assignee: Siecor Technology, Inc. (Corning Incorporated)
• Original Assignee: Northern Telecom Limited (Nortel Networks Corporation)
• Inventors: Caldwell, Kevin G., Seregelyi, Elza V., Lischynsky, Steve J.
• Primary Examiner(s): Healy, Brian
• Application Number:
  US07/385,844
• Time in Patent Office: 453 Days
• Field of Search: 350/96.20, 350/96.21, 350/96.22, 350/320, 65/4.1, 65/4.2, 65/4.3, 65/36, 156/158, 156/166, 156/155
• US Class Current: 385/56
• CPC Class Codes: G02B 6/32 having lens focusing means positioned between opposed fibre ends with lens being an integral part of the single fibre end G02B6/262
• CPC Class Codes: G02B 6/3825 with an intermediate part, e.g. adapter, receptacle, linking two plugs
• CPC Class Codes: G02B 6/3838 using grooves for light guides
• CPC Class Codes: G02B 6/3846 with fibre stubs
• CPC Class Codes: G02B 6/3847 with means preventing fibre end damage, e.g. recessed fibre surfaces
• CPC Class Codes: G02B 6/3874 using tubes, sleeves to align ferrules

Abstract

An optical fiber connector element comprises a connector body having a passage extending therethrough, the passage having a forward portion for receiving an optical fiber and a rearward portion which is wider than the forward portion for receiving an optical fiber and surrounding protective material, and an optical fiber stub secured within the forward portion of the passage, the optical fiber stub having a forward end surface which has an optical finish. The connector element is used to terminate an optical fiber cable by cutting the cable to a desired length, stripping back an end portion of protective material surrounding an optical fiber of the cable to expose an end portion of the optical fiber, and securing the exposed fiber end portion and an end portion of the protective material remaining on the fiber in the connector body passage with the fiber end portion in abutment and axial alignment with the fiber stub. The steps of securing the fiber stub within the connector body passage, trimming the forward end portion of the fiber stub and polishing the forward end surface of the fiber stub may be performed under controlled factory conditions and the steps of cutting the cable to the desired length, stripping back the end portion of protective material, and securing the fiber end portion within the connector body passage may be performed under field conditions. The optical fiber connector element and its method of use avoid the need for polishing a fiber end to an optical finish under adverse field conditions.

Claims

1. An optical fiber connector element for terminating an optical fiber cable, the connector element comprising:

a ferrule having an axial bore extending therethrough;

an optical fiber stub secured within the axial bore of the ferrule, the stub having a forward end surface which has an optical finish and a projecting portion which projects rearward from the ferrule for splicing to an end portion of a fiber of the optical fiber cable; and

a cable mount part which is securable to the ferrule to extend rearward of the ferrule, the cable mount part comprising a base member and a cover member for mating with the base member to secure the projecting portion of the stub and the end portion of the fiber between the base member and the cover member, at least one of the base member and the cover member having a deformable material at a mating surface of that member for deforming to substantially surround the projecting portion of the stub and the end portion of the fiber when the cover member is mated with the base member.

2. An optical fiber connector element as defined in claim 1, wherein both the base member and the cover member have deformable material at respective mating surfaces.

3. An optical fiber connector element as defined in claim 1, wherein the deformable material comprises a layer of deformable adhesive.

4. An optical fiber connector element for terminating an optical fiber cable, the connector element comprising:

a ferrule having an outer surface formation and an axial bore extending therethrough;

an optical fiber stub secured within the axial bore of the ferrule, the stub having a forward end surface which has an optical finish and a projecting portion which projects rearward from the ferrule for splicing to an end portion of a fiber of the optical fiber cable; and

a cable mount part which is securable to the ferrule to extend rearward of the ferrule, the cable mount part comprising a base member and a cover member for mating with the base member to secure the projecting portion of the stub and the end portion of the fiber between the base member and the cover member, at least one of the base member and the cover member having a deformable material at a mating surface of that member for deforming to substantially surround the projecting portion of the stub and the ned portion of the fiber when the cover member is mated with the base member, and the base member and the cover member have inner surface formations which are complementary to the outer surface formation of the ferrule for mating with the outer surface formation of the ferrule to secure the ferrule to the base and cover members when the cover member is mated with the base member.

5. An optical fiber connector element for terminating an optical fiber cable, the connector element comprising:

a ferrule having an axial bore extending therethrough;

an optical fiber stub secured within the axial bore of the ferrule, the stub having a forward end surface which has an optical finish and a projecting portion which projects rearward from the ferrule for splicing to an end portion of a fiber of the optical fiber cable;

a cable mount part which is securable to the ferrule to extend rearward of the ferrule, the cable mount part comprising a base member and a cover member for mating with the base member to secure the projecting portion of the stub and the end portion of the fiber between the base member and the cover member, at least one of the base member and the cover member having a deformable material at a mating surface of that member for deforming to substantially surround the projecting portion of the stub and the end portion of the fiber when the cover member is mated with the base member; and

a crimp sleeve fitting over the base member and cover member when the cover member is mated with the base member.

6. A method for terminating a fiber optic cable with a fiber optic connector element, the method comprising:

providing a connector element comprising a ferrule having an axial bore, an optical fiber stub secured within the axial bore of the ferrule, projecting rearward from the ferrule and having a forward end surface having an optical finish, and matable base and a cover members, at least one of which has a deformable material at a mating surface of that member;

cutting the cable to a desired length;

stripping back an end portion of protective material surrounding an optical fiber of the cable to expose an end portion of the optical fiber;

splicing the fiber stub to the exposed fiber end portion; and

mating the base and cover members with the spliced fiber stub and fiber end portion between the base and cover members to deform the deformable material around the spliced fiber stub and fiber end portion and to secure the spliced fiber stub and fiber end portion between the mated base and cover members.

7. A method as defined in claim 6, wherein the splicing step comprises a fusion splicing operation.

8. A method for terminating a fiber optic cable with a fiber optic connector element, the method comprising:

providing a connector element comprising a ferrule having an axial bore, an optical fiber stub secured within the axial bore of the ferrule, projecting rearward from the ferrule and having a forward end surface having an optical finish, and matable base and a cover members, at least one of which has a deformable material at a mating surface of that member;

cutting the cable to a desired length;

stripping back an end portion of protective material surrounding an optical fiber of the cable to expose an end portion of the optical fiber;

splicing the fiber stub to the exposed fiber end portion;

mating the base and cover members with the spliced fiber stub and fiber end portion between the base and cover members to deform the deformable material around the spliced fiber stub and fiber end portion and to secure the spliced fiber stub and fiber end portion between the mated base and cover members;

fitting a crimp sleeve over the base member and cover member when the cover member is mated with the base member; and

compressing the crimp sleeve onto the mated cover member and base member.