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US4504949A
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Stimulated anti-Stokes Raman up-converter
Assignee: Nokia Bell Labs
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Filing: 1982-09-22
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Granted: 1985-03-12
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Expires: 2002-09-22
Abstract
Abstract An anti-Stokes Raman up-converter is disclosed which is capable of up-converting a variety of conventional laser sources. A metal-halide, for example, thallium chloride or thallium iodide, is employed as a lasing medium, and is photodissociated to create a population inversion in a metastable state of the metal ion. An excimer laser, for example, and ArF* or KrF* excimer laser, may be employed to photodissociate the metal-halide in accordance with the present invention. Alternatively, an excimer flashlamp, for example a ArF* or KrF* flashlamp, may be employed to photodissociate the metal-halide in accordance with the present invention. A conventional laser source, for example a CO 2 laser or any harmonic of a Nd:YAG laser, is subsequently employed to pump the population inversion from the metastable state to a virtual level near an intermediate state. Anti-Stokes Raman lasing occurs from this virtual state, where the lasing frequency is greater than the frequency of the conventional laser pump source.
Inventors
- 👤 Jonathan C. White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:21
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/30; H01S3/305
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
113 words
An anti-Stokes Raman up-converter comprising a metal-halide Raman lasing medium including a ground state, an intermediate state, and at least one metallic metastable state; means for photodissociating said metal-halide Raman lasing medium and creating a population inversion in a metastable state of the metallic atom; and a pump source capable of producing a lasing output at a first frequency, said metallic atom population inversion responsive to the pump source lasing output for moving said metallic atom population inversion from said metastable state to a virtual state near said intermediate state and producing as an output anti-Stokes Raman lasing emission at a second frequency, wherein said second frequency is greater than said first frequency.
Claim 2
Dependent Claim
113 words
An anti-Stokes Raman up-converter comprising a metal-halide Raman lasing medium including a ground state, an intermediate state, and at least one metallic metastable state; means for photodissociating said metal-halide Raman lasing medium and creating a population inversion in a metastable state of the metallic atom; and a pump source capable of producing a lasing output at a first frequency, said metallic atom population inversion responsive to the pump source lasing output for moving said metallic atom population inversion from said metastable state to a virtual state near said intermediate state and producing as an output anti-Stokes Raman lasing emission at a second frequency, wherein said second frequency is greater than said first frequency.
Claim 3
Dependent Claim
55 words
An anti-Stokes Raman up-converter formed in accordance with claim 1 wherein said up-converter further comprises time delay/synchronization means for separately initiating both the photodissociating means and the pump source such that the output from said photodissociating means arrives at the metal-halide Raman lasing medium a predetermined time interval before the output from said pump source.
Claim 4
Dependent Claim
21 words
An anti-Stokes Raman up-converter formed in accordance with claims 1 or 2 wherein the photodissociating means comprises an excimer lasing source.
Claim 5
Dependent Claim
20 words
An anti-Stokes Raman up-converter formed in accordance with claim 3, wherein the excimer pumping source comprises an ArF* excimer laser.
Claim 6
Dependent Claim
20 words
An anti-Stokes Raman up-converter formed in accordance with claim 3 wherein the excimer pumping source comprises a KrF* excimer laser.
Claim 7
Dependent Claim
21 words
An anti-Stokes Raman up-converter formed in accordance with claims 1 or 2 wherein the photodissociating means comprises an excimer flashlamp source.
Claim 8
Dependent Claim
20 words
An anti-Stokes Raman up-converter formed in accordance with claim 6 wherein the excimer flashlamp source comprises an ArF* excimer flashlamp.
Claim 9
Dependent Claim
20 words
An anti-Stokes Raman up-converter formed in accordance with claim 6 wherein the excimer flashlamp source comprises a KrF* excimer flashlamp.
Claim 10
Dependent Claim
23 words
An anti-Stokes Raman up-converter formed in accordance with claims 1 or 2 wherein the metal-halide Raman lasing medium comprises a thallium halide compound.
Claim 11
Dependent Claim
19 words
An anti-Stokes Raman up-converter formed in accordance with claim 9 wherein the thallium halide compound comprises thallium chloride (TlCl).
Claim 12
Dependent Claim
19 words
An anti-Stokes Raman up-converter formed in accordance with claim 9 wherein the thallium halide compound comprises thallium iodide (TlI).
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-11 | 1988-09-10 | 1989-03-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-11 | 1992-09-10 | 1993-03-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-11 | 1996-09-10 | 1997-03-12 | $7700.00 | Window Closed / Lapsed |