(12) United States Patent Kourogi et al.

US007239442B2

US 7,239,442 B2 Jul. 3, 2007

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OPTICAL FREQUENCY COMB GENERATOR

Inventors: Motonobu Kourogi, 4-28-905, Wakabadai, Asahi-ku, Yokohama-shi, KanagaWa, 241-0801 (JP); Widiyatmoko Bambang, KanagaWa (JP); Osamu Nakamoto, Tokyo (JP); Shigeyoshi MisaWa, Tokyo (JP); Yoshinobu Nakayama, Tokyo (JP)

Assignees: Japan Science and Technology Agency (JP); Motonobu Kourogi (JP)

Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 117 days.

10/484,598 Jul. 26, 2002

Appl. No.:

PCT Filed:

PCT No.:

§ 371 (0X1)’ (2), (4) Date:

PCT/JP02/07637

Aug. 30, 2004

PCT Pub. No.: WO03/010596

PCT Pub. Date: Feb. 6, 2003

Prior Publication Data

US 2005/0018276 A1 Jan. 27, 2005

Foreign Application Priority Data

(JP) ........................... .. 2001-226588

(JP) ........................... .. 2001-226591

(JP) ........................... .. 2001-334299

(JP) 2001-354947 (JP) 2002-038839 (JP) ........................... .. 2002-097167

Int. Cl. H04B 10/17 (2006.01) US. Cl. ..................................... .. 359/346; 359/333

Field of Classi?cation Search .............. .. 359/333,

359/346 See application ?le for complete search history.

IL

(56) References Cited

U. S. PATENT DOCUMENTS

3,676,796 A * 7/1972 Weber ....................... .. 372/19

(Continued) FOREIGN PATENT DOCUMENTS

JP T94047 1/1996 JP 10-206919 8/1998 JP N99-0293 8/1998 JP 11-288009 10/1999

OTHER PUBLICATIONS

Saitoh et al. Modulation Characteristic of Waveguide-Type Optical Frequency Comb Generator. Journal of Lightwave Technology, vol. 16, No. 5, May 1998. 824-832.*

(Continued) Primary ExamineriJack Keith Assistant ExamineriAri M. Diacou (74) Attorney, Agent, or F irmiReed Smith, LLP

(57) ABSTRACT

An optical frequency comb generator includes an oscillator (117) for oscillating modulating signals of a preset fre quency, and an optical resonator (110) formed by an incident side re?ecting mirror (112) and an outgoing side re?ecting mirror (113), arranged parallel to each other. The optical resonator causes resonation in light incident via the incident side re?ecting mirror (112). The optical frequency comb generator also includes an optical phase modulation unit (111) arranged betWeen the incident side re?ecting mirror (112) and the outgoing side re?ecting mirror (113) for phase modulating the light, resonated by the optical resonator (110), by the modulating signals supplied from the oscillator (117), and for generating a plurality of sidebands centered about the frequency of the incident light at a frequency interval of the modulating signal. The outgoing side re?ect ing mirror (113) sets the transmittance from one frequency to another responsive to the light intensity of the generated sidebands.

28 Claims, 27 Drawing Sheets

10

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US 7,239,442 B2 Page 2

US. PATENT DOCUMENTS

4,989,201 A * 1/1991 Glance ...................... .. 398/95

5,153,933 A * 10/1992 Smith et al. 385/27 5,166,822 A * 11/1992 Priatko et al. .. 359/287

5,265,112 A * 11/1993 Noll et al. .... .. 372/32

5,663,822 A * 9/1997 Fee .............. .. 398/95

5,699,378 A * 12/1997 Lealman et a1. 372/102

6,163,553 A * 12/2000 Pfeiifer . . . . . . . . . . . . . . . . . .. 372/6

6,201,638 B1* 3/2001 Hall et a1. .. 359/346

6,487,329 B2* 11/2002 FoltZer 385/15 6,591,026 B2* 7/2003 Endo et al. 385/15 6,724,788 B1 * 4/2004 HolZWarth et a1. . 372/32

6,897,959 B2* 5/2005 Haensch et al. 356/432 2005/0254534 A1* 11/2005 Loewen et al. ............. .. 372/32

OTHER PUBLICATIONS

Arthur Lowery. Performance Predictions and Topology Improvements for Optical Serrodyne Comb Generators. Journal ofLightWave Technology, vol. 23, No. 8, Aug. 2005. 2371-2379.* In Kag HWang, Seok Hyun Yun, Byoung Yoon Kim. All ?ber nonreciprocal ?lter With wavelengthElEltunability. OFC ’98 Technical Digest. 336-338.* OptoComb technical datasheet/avertising brochure. Optical Frequency Comb Generator. BK-SM 625C / BK-SM 2500C. Optical Comb Institute, Inc. Tokyo Institute of Technology, Incubation Center R204, 2-12-1, O-okayama, Meguro-ku, Tokyo, 152-8550 Japan http://WWW.optocomb.com.* OptoComb technical datasheet/avertising brochure. Waveguide Optical Frequency Comb Generator. WTAS-01. Optical Comb Institute, Inc. Tokyo Institute of Technology, Incubation Center R204, 2-12-1, O-okayama, Meguro-ku, Tokyo, 152-8550 Japan http://WWW.optocomb.com.* M. Kourogi, T. Enami and M. Ohtsu. A Monolithic Optical Frequency Comb Generator. IEEE Photonics Technology Letters, vol. 6, No. 2, Feb. 1994. 214-217.* M. Kourogi, T. Enami, and M. Ohtsu. A Coupled-Cavity Monolithic Optical Frequency Comb Generator. IEEE Photonics Technology Letters, vol. 8, No. 12, Dec. 1996. 1698-1700.*

T. Saitoh, M. Kourogi, and M. Ohtsu. A Waveguide-Type Optical-Frequency Comb Generator. IEEE Photonics Tech nology Letters, vol. 7. No. 2, Feb. 1995. 197-199.* Jun Ye, Harald SchnatZ, and Leo W. Hollberg. Optical Frequency Combs: From Frequency Metrology to Optical Phase Control. IEEE Journal of Selected Topics in Quantum Electronics, vol. 9, No. 4, Jul/Aug. 2003. 1041-1058.* NeW Focus, Inc. Practical Uses and Applications of Electro Optic Modulators. Application Note 2, Rev C, Copyright 2001. http://WWW.neWfocus.com/OnlineiCatalog/Litera ture/apnote2.pdf. DLed: Jul. 5, 2006* K. Imai; M. Kourogi; M. Ohtsu;i30-THZ Span Optical Frequency Comb Generation by Self-Phase Modulation in an Optical Fiber, IEEE Journal Of Quantum Electronics, vol. 34, No. 1, Jan. 1998, pp. 54-60. M. Kourogi; T. Enami; M. Ohtsu;iA Coupled-Cavity Monolithic Optical Frequency Comb Generator, IEEE Photonics Technology Letters, vol. 8, No. 12, Dec. 1996, pp. 1698-1700. Jun Ye; Long-Sheng Ma; Timothy Daly; John L. Hall;iHighly selective terahertZ optical frequency comb generator, Optics Letters, vol. 22, No. 5, Mar. 1, 1997, pp. 301-303. M. Kourogi; T. Enami; M. Ohtsu;iA Monolithic Optical Frequency Comb Generator, IEEE Photonics Technology Letters, vol. 6, No. 2, Feb. 1994. International Preliminary Examination Report (Translation). K. Imai, M. Kourogi, M. Ohtsu “30-THZ Span Optical Frequency Comb Generation by Self-Phase Modulation in an Optical Fiber”, IEEE Journal Of Quantum Electronics, vol. 34, No. 1, Jan. 1998, pp. 54-60. M. Kourogi, T. Enami, M. Ohtsu “A Coupled-Cavity Mono lithic Optical Frequency Comb Generator”, IEEE Photonics Technology Letters, vol. 8, No. 12, Dec. 1996, pp. 1698 1700. M. Kourogi, T. Enami, M. Ohtsu “A Monolithic Optical Frequency Comb Generator”, IEEE Photonics Technology Letters, vol. 6, No. 2, Feb. 1994, pp. 214-217. European Search Report.

* cited by examiner

U.S. Patent Jul. 3, 2007 Sheet 1 0f 27 US 7,239,442 B2

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U.S. Patent Jul. 3, 2007 Sheet 9 0f 27 US 7,239,442 B2

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U.S. Patent Jul. 3, 2007 Sheet 12 0f 27 US 7,239,442 B2

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U.S. Patent Jul. 3, 2007 Sheet 13 0f 27 US 7,239,442 B2

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