OPTICAL PULSE AMPLIFIER AND OPTICAL PULSE SOURCE

• US 20090003394A1
• Filed: 06/10/2008
• Published: 01/01/2009
• Est. Priority Date: 06/28/2007
• Status: Active Grant

• Current Assignee: Furukawa Electric Company Limited
• Original Assignee: Furukawa Electric Company Limited
• Inventors: Matsushita, Shunichi, Oguri, Atsushi
• Granted Patent: US 8,275,010 B2
• Time in Patent Office: Days
• US Class Current: 372/25
• CPC Class Codes: H01S 3/0057 Temporal shaping, e.g. pulse compression, frequency chirping soliton generation and propagation G02F1/3513, H01S3/063 and H01S3/108
• CPC Class Codes: H01S 3/06704 Housings; Packages
• CPC Class Codes: H01S 3/06725 Fibre characterized by a specific dispersion, e.g. for pulse shaping in soliton lasers or for dispersion compensating [DCF]
• CPC Class Codes: H01S 3/06754 Fibre amplifiers H01S3/06708 takes precedence
• CPC Class Codes: H01S 3/06779 with optical power limiting
• CPC Class Codes: H01S 3/2316 Cascaded amplifiers

Abstract

The pulse light source according to the present invention comprises: a seed pulse generator 1 for outputting an input pulse 10 as a seed pulse; a pulse amplifier 2; and a dispersion compensator 3 for dispersion compensating a light pulse output from the pulse amplifier 2. Moreover, the pulse amplifier 2 comprises a normal dispersion medium (DCF 4) and an amplification medium (EDF 5) that are multistage-connected alternately, for changing the input pulse 10 to a light pulse having a linear chirp and outputting the light pulse. Furthermore, an absolute value of the dispersion of the DCF 4 becomes to be larger than the absolute value of the dispersion of the EDF 5.

Claims

1. A pulse amplifier comprising:

an amplification medium and a normal dispersion medium that are multistage-connected alternately, for changing an input pulse to a light pulse having a linear chirp in a bandwidth range of wider than that for the input pulse and outputting the light pulse.

2. The pulse amplifier of claim 1,

wherein the multistage-connected media include at least three in total of the amplified media and the normal dispersion media that are multistage-connected alternately.

3. The pulse amplifier of claim 1 or 2,

wherein the amplification medium is a rare earth doped optical fiber.

4. The pulse amplifier of claim 3,

wherein a dispersion of the rare earth doped optical fiber is a normal dispersion.

5. The pulse amplifier of any one of claims 1 to 4,

wherein an absolute value of the dispersion of the normal dispersion medium is larger than the absolute value of the dispersion of the amplification medium.

6. The pulse amplifier of any one of claims 1 to 5,

wherein the amplification medium and the normal dispersion medium are a polarization maintaining type.

7. The pulse amplifier of any one of claims 1 to 6,

wherein a time waveform of the light pulse having the linear chirp is parabolic functional.

8. The pulse amplifier of any one of claims 1 to 7,

wherein the normal dispersion media and the amplified media are multistage-connected as not less than three stages.

9. A pulse light source comprising:

a seed pulse generator for outputting a seed pulse; and

a pulse amplifier comprising an amplification medium and a normal dispersion medium that are multistage-connected alternately,

wherein the pulse amplifier changes an input pulse to a light pulse having a linear chirp in a bandwidth range of wider than that for the input pulse and outputs the light pulse.

10. The pulse light source of claim 9,

wherein the multistage-connected media include at least three in total of the amplified media and the normal dispersion media that are multistage-connected alternately.

11. The pulse light source of claim 9 or 10,

wherein the amplification medium is a rare earth doped optical fiber.

12. The pulse light source of claim 11,

wherein a dispersion of the rare earth doped optical fiber is a normal dispersion.

13. The pulse light source of any one of claims 9 to 12,

wherein an absolute value of the dispersion of the normal dispersion medium is larger than the absolute value of the dispersion of the amplification medium.

14. The pulse light source of any one of claims 9 to 13,

wherein the amplification medium and the normal dispersion medium are a polarization maintaining type.

15. The pulse light source of any one of claims 9 to 14,

wherein a time waveform of the light pulse having the linear chirp is parabolic functional.

16. The pulse light source of any one of claims 9 to 15,

wherein a full width at half maximum of the seed pulse output from the seed pulse generator is not less than two picoseconds.

17. The pulse light source of any one of claims 9 to 16,

wherein the seed pulse generator comprises a laser source of a direct modulating type for a semiconductor laser, as a seed pulse light source for outputting a seed pulse.

18. The pulse light source of claim 17,

wherein the laser source is a gain switch light source for gain switch driving the semiconductor laser.

19. The pulse light source of any one of claims 9 to 18, further comprising:

a dispersion compensator for further dispersion compensating a light pulse output from the pulse amplifier.

20. The pulse light source of claim 19,

wherein the dispersion compensator is an anomalous dispersion fiber.

21. The pulse light source of claim 19,

wherein the dispersion compensator is comprised of a grating pair.

22. The pulse light source of any one of claims 9 to 21,

wherein the normal dispersion media and the amplified media are multistage-connected as not less than three stages.