Multiwavelength light source using an optical parametric oscillator
| Title: | Multiwavelength light source using an optical parametric oscillator |
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| Patent Number: | 7,016,103 |
| Publication Date: | March 21, 2006 |
| Appl. No: | 10/363633 |
| Application Filed: | September 06, 2001 |
| Abstract: | An apparatus for generating at least three visible light beams of different output wavelengths for display purposes includes a passively mode-locked solid-state thin-disk laser and a device, including an optical parametric oscillator (OPO) for at least partially converting the primary light beam into electromagnetic radiation having the at least three different output wavelengths. The OPO is preferably an optical fiber feedback OPO. An optical fiber feedback OPO includes a nonlinear optical element and feedback device for feeding back at least a portion of the radiation emitted by the nonlinear medium to the nonlinear element. The feedback device includes an optical fiber. |
| Inventors: | Paschotta, Rudiger (Zürich, CH); Sudmeyer, Thomas (Zürich, CH); Weingarten, Kurt (Zürich, CH); Hanna, David C. (Southampton, GB) |
| Assignees: | Time-Bandwith Products AG (Zurich, CH) |
| Claim: | 1. An apparatus for generating at least three light beams of different output wavelengths comprising: a pulsed laser for emitting a primary light beam having a primary beam effective wavelength, means for at least partially converting said primary light beam into electromagnetic radiation having at least three different output wavelengths, wherein said means includes a fiber feedback optical parametric oscillator (OPO). |
| Claim: | 2. The apparatus according to claim 1 , wherein said optical parametric oscillator comprises an LBO nonlinear crystal. |
| Claim: | 3. The apparatus according to claim 1 , wherein said primary beam effective wavelength is between 980 nm and 1100 nm. |
| Claim: | 4. The apparatus according to claim 1 , wherein said means for at least partially converting said primary light beam further comprises at least one frequency doubling means and at least one sum frequency generating means. |
| Claim: | 5. The apparatus according to claim 4 , wherein said primary light beam source, said optical parametric oscillator (OPO), at least two frequency doubling means, light deflecting means, and dichroic elements are mutually arranged such that, if the primary light beam source emits electromagnetic radiation having an effective wavelength between 980 nm and 1100 nm: a first frequency doubling means produces green light by frequency doubling light of the primary light beam; the thus frequency doubled light is used for pumping said OPO; the residual pumping light of said OPO serving as green light output; blue light is generated by a first frequency sum generation means, of which the signal output of said OPO and residual primary light from said first frequency doubling means serve as input; and, red light is generated by a frequency sum generation means, of which the idler output of said OPO and residual primary light from said first frequency doubling means serve as input. |
| Claim: | 6. The apparatus according to claim 1 , wherein said primary light beam source, said optical parametric oscillator (OPO), at least two frequency doubling means, light deflecting means and dichroic elements are mutually arranged such that, if the primary light beam source emits electromagnetic radiation having an effective wavelength between 980 nm and 1100 nm: the OPO is directly pumped with said primary light beam and generates a signal and idler output; blue light is generated by frequency doubling the signal output in two subsequent frequency doubling means; red light is generated by frequency doubling the idler output in two subsequent frequency doubling means; and, green light is obtained from a frequency doubling means, which is directly pumped with a primary beam portion. |
| Claim: | 7. The apparatus of claim 6 , wherein said frequency doubling means for obtaining green light includes first frequency doubling means being pumped with the primary light beam and wherein the residual primary light beam portion from said first frequency doubling means is used for pumping the OPO. |
| Claim: | 8. The apparatus according to claim 1 , wherein said optical parametric oscillator comprises a plurality of nonlinear optical elements, and wherein at least some of the nonlinear optical elements allow operation at or near room temperature. |
| Claim: | 9. The apparatus according to claim 8 , wherein all of the nonlinear optical elements contained in the apparatus are selected so as to permit operation at or near room temperature. |
| Claim: | 10. The apparatus according to claim 8 , wherein at least some of the nonlinear optical elements are LBO crystals. |
| Claim: | 11. The apparatus according to claim 10 , wherein all nonlinear optical elements contained in the apparatus are LBO crystals. |
| Claim: | 12. The apparatus according to claim 1 , wherein one of said at least three different light beams generated is an unconverted proportion of said primary light beam, and wherein the output wavelength of said one light beam corresponds to the input wavelength. |
| Claim: | 13. The apparatus according to claim 1 , wherein at least one of said at least three light beams is an infrared light beam. |
| Claim: | 14. The apparatus according to claim 1 , wherein the pulsed laser is mode-locked. |
| Claim: | 15. The apparatus according to claim 14 , wherein the pulsed, mode-locked laser is a solid state thin-disk laser. |
| Claim: | 16. An apparatus for generating at least three visible light beams of different output wavelengths comprising: a short-pulse high average power laser for emitting a primary light beam having a primary beam effective wavelength; means for at least partially converting said primary light beam into electromagnetic radiation having at least three different output wavelengths, said means including a fiber feedback optical parametric oscillator (OPO). |
| Claim: | 17. The apparatus according to claim 16 , wherein the laser for emitting a primary light beam comprises means for generating sub-picosecond pulses. |
| Claim: | 18. The apparatus according to claim 16 , wherein the laser for emitting a primary light beam is designed such that it can be operated at average output powers exceeding 50 W. |
| Claim: | 19. The apparatus according to claim 16 , wherein said optical parametric oscillator comprises a plurality of nonlinear optical elements, and wherein at least some of the optically nonlinear elements permit operation at or near room temperature. |
| Claim: | 20. The apparatus according to claim 19 , wherein all of the nonlinear optical elements of the apparatus permit operation at or near room temperature. |
| Claim: | 21. The apparatus according to claim 19 , wherein all nonlinear optical elements of the apparatus are LBO crystals. |
| Claim: | 22. The apparatus according to claim 16 , wherein at least some of the nonlinear optical elements are LBO crystals. |
| Claim: | 23. The apparatus according to claim 16 , wherein said primary light beam source, said optical parametric oscillator (OPO), at least two frequency doubling means and light deflecting means and dichroic elements are mutually arranged such that, if the primary light beam source emits electromagnetic radiation characterized by an effective wavelength between 980 nm and 1100 nm: a first frequency doubling means produces green light by frequency doubling light of the primary light beam; the thus frequency doubled light is used for pumping said OPO; the residual pumping light of said OPO serving as green light output; blue light is generated by a first frequency sum generation means, of which the signal output of said OPO and residual primary light from said first frequency doubling means serve as input; and, red light is generated by a frequency sum generation means, of which the idler output of said OPO and residual primary light from said first frequency doubling means serve as input. |
| Claim: | 24. The apparatus according to claim 16 , wherein said primary light beam source, said optical parametric oscillator (OPO), at least two frequency doubling means and light deflecting means and dichroic elements are mutually arranged such that, if the primary light beam source emits electromagnetic radiation characterized by an effective wavelength between 980 nm and 1100 nm: the OPO is directly pumped with said primary light beam and generates a signal and idler output; blue light is generated by frequency doubling the signal output in two subsequent frequency doubling means; red light is generated by frequency doubling the idler output in two subsequent frequency doubling means; and, green light is obtained from a frequency doubling means, which is directly pumped with a primary beam portion. |
| Claim: | 25. The apparatus according to claim 24 , wherein said frequency doubling means for obtaining green light includes first frequency doubling means being pumped with the primary light beam, and wherein the residual primary light beam portion from said first frequency doubling means is used for pumping the OPO. |
| Claim: | 26. The apparatus according to claim 16 , wherein said primary beam effective wavelength is between 980 nm and 1100 nm. |
| Claim: | 27. The apparatus according to claim 16 , wherein one of said at least three different light beams generated is an unconverted proportion of said primary light beam, and wherein the output wavelength of said one light beam corresponds to the input wavelength. |
| Claim: | 28. A method of generating at least three light beams of different output wavelengths comprising the steps of: producing a continuous train of picosecond or sub-picosecond pulses of primary laser light characterized by a primary beam effective wavelength; and, at least partially converting, using non-linear optical elements, said primary light beam into electromagnetic radiation having at least three different output wavelengths; wherein said at least partially converting said primary light beam includes producing a signal beam and an idler beam in an Optical Parametric Oscillator (OPO) including the steps of: exciting, by laser light pumping, a non-linear optical element placed in an optical resonator to emit at least a signal beam and an idler beam of coherent electromagnetic radiation; and, partially feeding back said idler beam into said non-linear optical element using an optical fiber. |
| Claim: | 29. The method according to claim 28 , wherein said primary beam effective wavelength is between 980 nm and 1100 nm. |
| Claim: | 30. The method according to claim 29 , wherein: green light is produced by frequency doubling light of the primary light beam; the thus frequency doubled green light is used for pumping said OPO; the residual pumping light of said OPO serving as green light output; blue light is produced, using a non-linear optical element and phase matching techniques, by generating a sum frequency beam of the signal output of said OPO and residual primary light from said first frequency doubling means; and, red light is produced, using a non-linear optical element and phase matching techniques, by generating a sum frequency beam of the idler output of said OPO and residual primary light from said first frequency doubling means. |
| Claim: | 31. The method according to claim 29 , wherein: the OPO is directly pumped with said primary light beam and generates a signal output and an idler output; blue light is generated by twice frequency doubling the signal output; red light is generated by twice frequency doubling the idler output; and, green light is obtained by frequency doubling a primary beam portion. |
| Claim: | 32. The method according to claim 31 , wherein residual primary light beam portion from producing the green light is used for pumping the OPO. |
| Claim: | 33. The method according to claim 28 , wherein said optical parametric oscillator comprises a plurality of nonlinear optical elements, and wherein said non-linear optical elements are operated at or near room temperature. |
| Claim: | 34. A device for emitting electromagnetic radiation when being optically pumped by coherent electromagnetic radiation having by an input beam wavelength, the input beam wavelength and at least two output beam wavelengths of the emitted electromagnetic radiation being mutually different, the device comprising a nonlinear optical element and feedback means for feeding back at least a portion of the radiation emitted by the nonlinear medium to the nonlinear element, wherein the feedback means comprise an optical fiber. |
| Claim: | 35. The device according to claim 34 , wherein the nonlinear medium has two end faces, radiation characterized by said at least two output beam wavelengths being emitted through a first one of said end faces, and the feedback means and the nonlinear element being arranged such that radiation emitted through said first end face is fed back through a second one of said two end faces. |
| Claim: | 36. The device according to claim 34 , wherein said optical fiber is a single mode optical fiber. |
| Claim: | 37. The device according to claim 36 , wherein the diameter, the refractive index, and in-coupling means of said optical fiber are such that radiation characterized by the shorter one of said at least two output wavelength, a signal wavelength, is fed back to the nonlinear medium. |
| Claim: | 38. The device according to claim 34 , wherein the fiber is a standard telecom optical glass fiber. |
| Claim: | 39. The device according to claim 34 , wherein said device does not include active controlling means for stabilizing the length of the feedback path. |
| Claim: | 40. The device according to claim 34 , wherein the nonlinear optical element is a χ 2 nonlinear optical element. |
| Claim: | 41. A device for generating output electromagnetic radiation having at least two different output beam wavelengths, comprising: a pumping beam pulse laser for emitting coherent electromagnetic radiation having a pumping beam wavelength and a beam path, the pumping beam wavelength and said at least two output beam wavelengths being mutually different; a nonlinear optical element placed in the beam path of the pumping beam; and, feedback means for feeding back at least a portion of the radiation emitted by the nonlinear medium to the nonlinear element, wherein the feedback means comprise an optical fiber. |
| Claim: | 42. A method of generating electromagnetic radiation having at least two different output beam wavelengths using a continuous train of picosecond or sub-picosecond pulses of input coherent electromagnetic radiation having an input beam effective wavelength, comprising the steps of: directing said input coherent electromagnetic radiation onto a non-linear optical element such that output electromagnetic radiation is produced; and, feeding back a portion of said output electromagnetic radiation to said non-linear optical element using a glass fiber; wherein said portion of said output electromagnetic radiation includes a single one of said output beam wavelengths. |
| Claim: | 43. The method according to claim 42 , wherein the non-linear optical element has two end faces, and wherein radiation of said at least two output beam wavelengths being emitted through a first one of said end faces, and wherein radiation emitted through said first end face is fed back through a second one of said two end faces. |
| Current U.S. Class: | 359/330 |
| Patent References Cited: | 5828424 October 1998 Wallenstein 5894489 April 1999 Halldorsson et al. 6154310 November 2000 Galvanauskas et al. 6233089 May 2001 Nebel 6480325 November 2002 Batchko et al. 2004/0075883 April 2004 Galvanauskas et al. |
| Other References: | Au Aus der J et al: “16.2-W Average Power From a Diode-pumped Femtosecond Yb: YAG Thin Disk Laser”, Optics Letters, Optical Society of America, Washington, US, vol. 25, No. 11, Jun. 1, 2000 pp. 859-861, XP000951881. cited by other Sudmeyer T et al: “Femtosecond fiber-feedback optical parametric oscillator”, Optics Letters, Mar. 1, 2001, Opt. Soc. America, USA, vol. 26, No. 5, pp. 304-306, XP002198272. cited by other |
| Primary Examiner: | Lee, John D. |
| Attorney, Agent or Firm: | Rankin, Hill, Porter & Clark LLP |
| Accession Number: | edspgr.07016103 |
| Database: | USPTO Patent Grants |
| Language: | English |
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