System and method for generating supercontinuum light

• US 20060268393A1
• Filed: 01/20/2006
• Published: 11/30/2006
• Est. Priority Date: 01/21/2005
• Status: Abandoned Application

• Current Assignee: Omni Sciences Incorporated
• Original Assignee: Omni Sciences Incorporated
• Inventors: Islam, Mohammed N.
• Application Number:
  US11/335,998
• Publication Number:
  US 20060268393A1
• Time in Patent Office: Days
• US Class Current: 359/337.500
• CPC Class Codes: G02F 1/3528 for producing a supercontinuum
• CPC Class Codes: G02F 1/353 Frequency conversion, i.e. wherein a light beam is generated with frequency components different from those of the incident light beams
• CPC Class Codes: G02F 1/365 in an optical waveguide structure G02F1/377, G02F1/395 take precedence

Abstract

A supercontinuum light source includes a modulated pump laser, a first fiber, and a nonlinear waveguide. The modulated pump laser generates light comprising longer pulses, where a longer pulse has a temporal duration of approximately ten picoseconds or more. The first fiber breaks at least one longer pulse into shorter pulses, where a shorter pulse has a temporal duration of approximately two picoseconds or less. The first fiber at least partially operates in an anomalous group velocity dispersion regime, and the shorter pulses result from a modulational instability in the first fiber. The nonlinear waveguide spectrally broadens the shorter pulses to yield supercontinuum light, where the supercontinuum light has a spectral width of approximately 150 nanometers or more.

Claims

1. A supercontinuum light source, comprising:

a modulated pump laser operable to;

generate light comprising a plurality of longer pulses, a longer pulse of the plurality of longer pulses having a temporal duration of approximately ten picoseconds or more;

a first fiber coupled to the modulated pump laser, the first fiber at least partially operating in an anomalous group velocity dispersion regime, the first fiber operable to;

break at least one longer pulse of the plurality of longer pulses into a plurality of shorter pulses, a shorter pulse of the plurality of shorter pulses having a temporal duration of approximately two picoseconds or less, the plurality of shorter pulses resulting from a modulational instability in the first fiber; and

a nonlinear waveguide coupled to the first fiber, the nonlinear waveguide operable to;

spectrally broaden at least some of the plurality of shorter pulses to yield supercontinuum light, the supercontinuum light having a spectral width of approximately 150 nanometers or more.

2. The supercontinuum light source of claim 1, wherein the modulated pump laser comprises:

one or more laser diodes coupled to an optical amplifier.

3. The supercontinuum light source of claim 1, wherein the modulated pump laser comprises:

one or more laser diodes, at least one laser diode of the laser diodes comprising a distributed feedback laser.

4. The supercontinuum light source of claim 1, wherein the modulated pump laser further comprises an amplifier selected from a group consisting of:

an erbium-doped fiber amplifier, a Raman amplifier, a semiconductor amplifier, and a rare-earth doped fiber amplifier.

5. The supercontinuum light source of claim 1, wherein the modulated pump laser comprises:

a filtering system operable to reduce amplified spontaneous emission.

6. The supercontinuum light source of claim 1, wherein the modulated pump laser comprises:

a filtering system operable to reduce amplified spontaneous emission, the filtering system comprising;

one or more wavelength filters; and

at least one temporal modulator substantially synchronized with the plurality of longer pulses.

7. The supercontinuum light source of claim 1, wherein the plurality of longer pulses have a wavelength of approximately 1.4 to 1.7 microns or more.

8. The supercontinuum light source of claim 1, wherein the plurality of longer pulses have a temporal duration of approximately 100 picoseconds or more.

9. The supercontinuum light source of claim 1, wherein the plurality of longer pulses have a temporal duration of approximately one nanosecond or more.

10. The supercontinuum light source of claim 1, wherein the first fiber is selected from a group consisting of:

a fused silica fiber, a high-nonlinearity fiber, an optical amplifier, an erbium-doped fiber, a photonic crystal fiber, a dispersion compensating fiber, a dispersion shifted fiber, a non-zero dispersion fiber, a dispersion flattened fiber, a patch-cord fiber, and a low bend loss fiber.

11. The supercontinuum light source of claim 1, wherein the nonlinear waveguide is selected from a group consisting of:

a small core fiber, a high-nonlinearity fiber, a photonic crystal fiber, a fluoride fiber, and a chalcogenide fiber.

12. The supercontinuum light source of claim 1, wherein the nonlinear waveguide is selected from a group consisting of:

a semiconductor waveguide and a tellurite fiber.

13. The supercontinuum light source of claim 1, wherein the nonlinear waveguide has a core size of approximately 30 microns or less.

14. A supercontinuum light source comprising:

a modulated pump laser operable to;

generate light comprising a plurality of longer pulses, a longer pulse of the plurality of longer pulses having a temporal duration of approximately ten picoseconds or more;

a first fiber coupled to the modulated pump laser, the first fiber at least partially operating in an anomalous group velocity dispersion regime, the first fiber operable to;

break at least one longer pulse of the plurality of longer pulses into a plurality of shorter pulses, a shorter pulse of the plurality of shorter pulses having a temporal duration of approximately two picoseconds or less, the plurality of shorter pulses resulting from a modulational instability in the first fiber; and

a nonlinear waveguide coupled to the first fiber, the nonlinear waveguide operable to;

spectrally broaden at least some of the plurality of shorter pulses to yield supercontinuum light, the supercontinuum light having a time-averaged spectral density of approximately −

26 dBm/nm or more over at least a portion of a spectrum of the light.

15. The supercontinuum light source of claim 14, wherein the modulated pump laser further comprises an amplifier selected from a group consisting of:

an erbium-doped fiber amplifier, a Raman amplifier, a semiconductor amplifier, and a rare-earth doped fiber amplifier.

16. The supercontinuum light source of claim 14, further comprising:

an output operable to provide the supercontinuum light to an optical interferometer of an optical imaging system, the optical imaging system having a resolution of approximately 10 microns or less.

17. The supercontinuum light source of claim 14, further comprising:

an output operable to provide the supercontinuum light to a Michelson interferometer of an optical coherence tomography system, the optical coherence tomography system having a resolution of approximately 10 microns or less.

18. A method for generating supercontinuum light, comprising:

generating light comprising a plurality of longer pulses, a longer pulse of the plurality of longer pulses having a temporal duration of approximately ten picoseconds or more;

breaking at least one longer pulse of the plurality of longer pulses into a plurality of shorter pulses at a first fiber, a shorter pulse of the plurality of shorter pulses having a temporal duration of approximately two picoseconds or less, the first fiber at least partially operating in an anomalous group velocity dispersion regime, the plurality of shorter pulses resulting from a modulational instability in the first fiber; and

spectrally broadening at least some of the plurality of shorter pulses at a nonlinear waveguide to yield supercontinuum light, the supercontinuum light having a spectral width of approximately 150 nanometers or more.

19. The method of claim 18, wherein generating light comprising the plurality of longer pulses further comprises:

amplifying light generated by one or more laser diodes; and

filtering the amplified light to reduce amplified spontaneous emission.

20. The method of claim 18, wherein the nonlinear waveguide is selected from a group consisting of:

a small core fiber, a high-nonlinearity fiber, a photonic crystal fiber, a fluoride fiber, and a chalcogenide fiber.