Dispersion compensator and optical transmission system

• US 20010051031A1
• Filed: 03/13/2001
• Published: 12/13/2001
• Est. Priority Date: 03/13/2000
• Status: Active Grant

• Current Assignee: Keiichiro Fukuda, Kenji Tamano, Kohei Kobayashi, Masashi Onishi, Mitsuomi Hada
• Original Assignee: Keiichiro Fukuda, Kenji Tamano, Kohei Kobayashi, Masashi Onishi, Mitsuomi Hada
• Inventors: Onishi, Masashi, Tamano, Kenji, Kobayashi, Kohei, Hada, Mitsuomi, Fukuda, Keiichiro
• Granted Patent: US 6,628,872 B2
• Time in Patent Office: Days
• US Class Current: 385/123
• CPC Class Codes: G02B 6/29376 coupling light guides for controlling wavelength dispersion, e.g. by concatenation of two light guides having different dispersion properties dispersion managed optical transmission systems H04B10/25253
• CPC Class Codes: H04B 10/2525 using dispersion-compensating fibres

Abstract

There is disclosed a dispersion compensator for compensating for a chromatic dispersion and dispersion slope of an optical fiber transmission line, the dispersion compensator comprising a plurality of dispersion-compensating optical fibers connected to each other, the dispersion-compensating optical fibers each having a dispersion slope compensation ratio of at least 60% with respect to the optical fiber transmission line at a predetermined wavelength, one of said plurality of dispersion-compensating optical fibers having a dispersion slope compensation ratio of at least 80%, another of said plurality of dispersion-compensating optical fibers having a dispersion slope compensation ratio within the range of 60% to 100%.

Claims

1. A dispersion compensator for compensating for a chromatic dispersion and dispersion slope of an optical fiber transmission line;

said dispersion compensator comprising a plurality of dispersion-compensating optical fibers connected to each other, said dispersion-compensating optical fibers each having a dispersion slope compensation ratio of at least 60% with respect to said optical fiber transmission line at a predetermined wavelength;

one of said plurality of dispersion-compensating optical fibers having a dispersion slope compensation ratio of at least 80%;

another of said plurality of dispersion-compensating optical fibers having a dispersion slope compensation ratio within the range of 60% to 100%.

2. A dispersion compensator according to

claim 1

, wherein said plurality of dispersion-compensating optical fibers in total have an average dispersion slope compensation ratio of at least 80%.

3. A dispersion compensator according to

claim 1

, wherein said plurality of dispersion-compensating optical fibers are connected in the order of increasing effective area thereof.

4. A dispersion compensator according to

claim 1

, wherein, of said plurality of dispersion-compensating optical fibers, first and second dispersion-compensating optical fibers cascaded to each other are fusion-spliced.

5. A dispersion compensator according to

claim 4

, wherein the fusion-spliced portion between said first and second dispersion-compensating optical fibers is re-coated with a resin material having a coating diameter substantially equal to the coating diameter of each of said first and second dispersion-compensating optical fibers, and is wound on a bobbin together with said first and second dispersion-compensating optical fibers.

6. A dispersion compensator according to

claim 4

, wherein the fusion-spliced portion between said first and second dispersion-compensating optical fibers is re-coated with a resin material and is secured with reinforcement means.

7. A dispersion compensator according to

claim 4

, wherein said plurality of dispersion-compensating optical fibers are contained in a bundle state free of any body portion substantially in contact therewith.

8. A dispersion compensator according to

claim 3

, wherein said plurality of dispersion-compensating optical fibers are connected in the order of increasing dispersion compensation ratios thereof.

9. A dispersion compensator according to

claim 3

, wherein said plurality of dispersion,-compensating optical fibers are connected in the order of increasing dispersion compensation ratios thereof, and a signal light is input to an input end of said dispersion-compensating fiber of said plurality of dispersion-compensating fibers, having a larger effective area and smaller dispersion slope compensation ratio.

10. An optical transmission system comprising:

an optical fiber transmission line for transmitting signal light; and

the dispersion compensator of

claim 1

, comprising a plurality of dispersion-compensating optical fibers connected to each other, for compensating for the chromatic dispersion and dispersion slope of said optical fiber transmission line.

11. An optical transmission system according to

claim 8

, wherein said plurality of dispersion-compensating optical fibers are connected in the order of increasing effective area thereof, and signal light is fed from the side of the dispersion-compensating optical fiber having a larger effective area.

12. An optical transmission system according to

claim 10

, wherein said plurality of dispersion-compensating optical fibers are connected in the order of increasing dispersion compensation ratios thereof, and a signal light is input to an input end of said dispersion-compensating fiber of said plurality of dispersion-compensating fibers, having a larger effective area, and an exciting light for causing Raman amplification is input to an input end of said dispersion-compensating fiber of said plurality of dispersion-compensating fibers, hating a smaller effective area.