OPTICAL COUPLER INCLUDING MODE-MIXING
A mode-mixer is used to introduce mode-mixing to an input in an optical coupler. As a result, modal noise effects are minimized in an output of the optical coupler. An example of a mode-mixer implemented includes a step index optical fiber which may or may not be coupled to a graded index optical fiber via a splice within an optical coupler. The splice may be a mechanical splice using connectors or a fused splice in some embodiments. The optical coupler may be included in a system for monitoring and/or analyzing a network.
1 . An optical coupler comprising:
an input;
means for introducing mode-mixing optically coupled to the input;
a first output;
a second output; and
a fiber optic splitter configured to optically couple the input with the first output and the second output.
2 . An optical coupler according to claim 1 , wherein the means for introducing mode-mixing includes a step index optical fiber.
3 . An optical coupler according to claim 2 , wherein the input includes a graded index optical fiber, wherein the input further includes means for coupling optical energy between the step index optical fiber and the graded index optical fiber.
4 . An optical coupler according to claim 3 , wherein the means for coupling optical energy includes an optical fiber splice between the step index optical fiber and the graded index optical fiber.
5 . An optical coupler according to claim 4 , wherein the optical fiber splice includes a fusion splice between the step index optical fiber and the graded index optical fiber.
6 . An optical coupler according to claim 4 , wherein the optical fiber splice includes a mechanical splice between the step index optical fiber and the graded index optical fiber.
7 . An optical coupler according to claim 6 , wherein the mechanical splice includes a mated plug assembly between the step index optical fiber and the graded index optical fiber.
8 . An optical coupler according to claim 7 , wherein the mated plug assembly includes mated LC type optical connectors.
9 . An optical coupler according to claim 1 , wherein the first output includes a step index optical fiber.
10 . An optical coupler according to claim 1 , wherein the second output includes a step index optical fiber.
11 . An optical coupler according to claim 1 , wherein the optical coupler is associated with a predetermined split ratio.
12 . An optical coupler according to claim 11 , wherein the split ratio is between about 10:90 and 50:50.
13 . An optical coupler according to claim 11 , wherein the split ratio is about 20:80.
14 . An optical coupler according to claim 11 , wherein the split ratio is about 30:70.
15 . An optical coupler according to claim 2 , wherein a length of the step index optical fiber is at least about 2 centimeters.
16 . An optical coupler according to claim 2 , wherein a length of the step index optical fiber is between about 5 centimeters and about 100 centimeters.
17 . An optical coupler according to claim 2 , wherein a length of the step index optical fiber is between about 10 centimeters and about 20 centimeters.
18 . An optical coupler according to claim 2 , wherein a core diameter of the step index optical fiber is between about 25 and about 200 micron.
19 . An optical coupler according to claim 2 , wherein a core diameter of the step index optical fiber is about 50 micron.
20 . An optical coupler according to claim 2 , wherein a core diameter of the step index optical fiber is about 62.5 micron.
21 . An optical coupler according to claim 1 , wherein the first output includes a first output optical fiber, the second output includes a second output optical fiber, and the input includes an input optical fiber.
22 . An optical coupler according to claim 1 , wherein the means for introducing mode-mixing includes an attenuation device, surface coating, surface treatment, mechanical or optical perturbation, a doped fiber, or a roughness to a surface.
23 . A Fibre Channel tap comprising the optical coupler according to claim 1 .
24 . A Fibre Channel tap comprising at least two optical couplers according to claim 1 and configured to support up to 10 gigabits-per-second.
25 . A Fibre Channel tap comprising between about four and about 32 optical couplers according to claim 1 .
26 . A system comprising:
an optical coupler comprising:
an input;
means for introducing mode-mixing optically coupled to the input;
a first output;
a second output; and
a fiber optic splitter configured to optically couple the input with the first output and the second output;
a first electronic device optically coupled to the input of the optical coupler; and
a second electronic device optically coupled to the second output of the optical coupler.
27 . A system according to claim 26 , wherein the means for introducing mode-mixing includes a step index fiber.
28 . A system according to claim 26 , wherein the first electronic device includes a network host device and the second electronic device includes a network switch device.
29 . A system according to claim 26 , further comprising an analysis device coupled to the first output, the analysis device being configured to monitor and/or analyze data transmitted from the first electronic device to the second electronic device.
30 . A system according to claim 29 , wherein the analysis device includes a probe configured to monitor and/or analyze data transmitted from the first electronic device to the second electronic device at line rates of at least 4 gigabits-per-second.
31 . A method for processing an optical signal transmitted in an optical communication link, the method comprising:
introducing mode-mixing to the optical signal; and
diverting a portion of the optical signal transmitted in the optical communication link.
32 . A method according to claim 31 , wherein the diverted portion of the optical signal has a waveform that substantially represents a waveform of the optical signal transmitted in the optical communication link.
33 . A method according to claim 31 , further comprising:
converting the diverted portion of the optical signal to an electrical signal; and
outputting the electrical signal to an electronic device.
34 . A method according to claim 31 , wherein the optical signal transmitted in the optical communication link is associated with a transmission rate of at least about 4 gigabits-per-second.
35 . A method for analyzing an optical signal, comprising:
performing the acts of claim 31 ; and
analyzing the diverted portion of the optical signal.
36 . A method according to claim 35 , wherein the received optical data is analyzed for a mask margin associated with the received optical data.
37 . A method according to claim 36 , wherein the mask margin includes less than 5 percent mask degradation.
38 . A method according to claim 35 , wherein the analysis includes analysis of a network within which the optical data is transmitted.