Loop back plug and method

• US 8,041,178 B2
• Filed: 07/20/2009
• Issued: 10/18/2011
• Est. Priority Date: 04/19/2005
• Status: Expired due to Fees

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: ADC Telecommunications Incorporated (TE Connectivity Limited)
• Inventors: Gniadek, Jeffery, Reagan, Randy, Lu, Yu, Noonan, Michael
• Primary Examiner(s): Peng; Charlie
• Assistant Examiner(s): Radkowski; Peter
• Application Number:
  US12/505,862
• Publication Number:
  US 20100014824A1
• Time in Patent Office: 820 Days
• Field of Search: 385/16, 385/49, 385/52, 385/55
• US Class Current: 385/147
• CPC Class Codes: G01M 11/33 with a light emitter being disposed at one fibre or waveguide end-face, and a light receiver at the other end-face
• CPC Class Codes: G02B 6/3823 containing surplus lengths, internal fibre loops provisionally see also G02B6/444
• CPC Class Codes: G02B 6/3827 Wrap-back connectors, i.e. containing a fibre having an U shape
• CPC Class Codes: G02B 6/3849 using mechanical protective elements, e.g. caps, hoods, sealing membranes G02B6/3816 takes precedence; provisionally see H01R13/44
• CPC Class Codes: G02B 6/385 Accessories for testing or observation of connectors means for centering or aligning the light guide within the ferrule with auxiliary facilities for movably aligning or adjusting the fibre within its ferrule, measuring position, eccentricity G02B6/3843; mechanical features associated with the optical testing of optical fibres G01M11/088
• CPC Class Codes: G02B 6/3878 comprising a plurality of ferrules, branching and break-out means
• CPC Class Codes: G02B 6/3885 Multicore or multichannel optical connectors, i.e. one single ferrule containing more than one fibre, e.g. ribbon type optical ribbon cable G02B6/4403, G02B6/448
• CPC Class Codes: G02B 6/3895 identification of connection, e.g. right plug to the right socket or full engagement of the mating parts keying element on the plug or adapter G02B6/3831; keying element on the ferrule G02B6/3851; keying element for electrical connection H01R13/64
• CPC Class Codes: G02B 6/3897 Connectors fixed to housings, casing, frames or circuit boards G02B6/44528 takes precedence
• CPC Class Codes: G02B 6/4472 Manifolds
• CPC Class Codes: G02B 6/4473 Three-way systems
• CPC Class Codes: G02B 6/4475 with provision for lateral branching G02B6/4431 takes precedence
• CPC Class Codes: G02B 6/562 locatable, e.g. using magnetic means

Abstract

A loop back connector and methods for testing lines in a fiber optic network are disclosed. The loop back connector includes a ferrule having an interface side constructed for optical connection to a multifiber optical cable. The loop back connector also includes first and second optical loop back paths, each having first and second terminal ends positioned at the interface side. The terminal ends of each loop back path are adapted to be aligned to fibers in the multifiber optical cable. The method includes injecting a signal on a first optical path at a first location, looping back the signal at a second location onto a second optical path, and receiving the signal on the second optical path at the first location.

Claims

1. A loop back plug comprising:

a plug body having an optical connection end portion and an oppositely disposed terminal end portion, the terminal end portion having a blind end that is a non-optical-pass-through end;

a ferrule structure supported at the optical connection end portion of the plug body, the ferrule structure having an interface side that faces outward from the optical connection end portion of the plug body;

a first optical loop back path having first and second terminal ends positioned at the interface side of the ferrule structure; and

a second optical loop back path having first and second terminal ends positioned at the interface side of the ferrule structure.

2. The loop back plug of claim 1, wherein the ferrule structure includes alignment features.

3. The loop back plug of claim 2,

wherein the alignment features are guide pins that project outwardly from the optical connection end portion of the plug body.

4. The loop back plug of claim 1, further comprising a planar lightwave circuit, wherein the first and second optical loop back paths are disposed in the planar lightwave circuit.

5. The loop back plug of claim 4, wherein the planar lightwave circuit is mounted in the ferrule structure.

6. The loop back plug of claim 5, wherein the planar lightwave circuit floats within a receptacle of the ferrule structure.

7. The loop back plug of claim 1, wherein a predetermined insertion loss is fabricated into at least one of the first and second optical loop back paths.

8. The loop back connector of claim 7, wherein the predetermined insertion loss is wavelength-sensitive.

9. The loop back connector of claim 7, wherein the first and second optical loop back paths have a consistent insertion loss.