Patent US4095122A successfully refreshed from Google Patents.
US4095122A
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Tunable infrared and far-infrared source by four-photon mixing
Assignee: AT&T Inc
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Filing: 1977-08-04
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Granted: 1978-06-13
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Expires: 1997-08-04
Abstract
Abstract The invention relates to a high-power tunable infrared source employing a four-photon mixing process, with three input lasers, in which process the output power is resonantly enhanced by exciton states in the conversion medium.
Inventors
- 👤 Theodoar Charlouis Damen
- 👤 Erich Gornik
- 👤 Van-Tran Nguyen
- 👤 Chandra Kumar Naranbhai Patel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:37
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/353; G02F1/3534
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
130 words
An apparatus for generating tunable infrared radiation comprising first, second and third input lasers generating input beams of frequency ω 1 , ω 2 and ω 3 , respectively a nonlinear interaction medium comprising a crystal having exciton states, means for directing said input beams collinearly into said nonlinear interaction medium, whereby an output frequency ω 4 is generated, where ω.sub.4 = ω.sub.1 + ω.sub.2 - ω.sub.3, in which apparatus ω 1 and ω 2 are selected such that ω 1 is close to the frequency of a single-photon exciton state and the sum of ω 1 and ω 2 is very close to the frequency of a two photon exciton state, so that the output power of frequency ω 4 is resonantly enhanced by both of said exciton states.
Claim 2
Independent Claim
130 words
An apparatus for generating tunable infrared radiation comprising first, second and third input lasers generating input beams of frequency ω 1 , ω 2 and ω 3 , respectively a nonlinear interaction medium comprising a crystal having exciton states, means for directing said input beams collinearly into said nonlinear interaction medium, whereby an output frequency ω 4 is generated, where ω.sub.4 = ω.sub.1 + ω.sub.2 - ω.sub.3, in which apparatus ω 1 and ω 2 are selected such that ω 1 is close to the frequency of a single-photon exciton state and the sum of ω 1 and ω 2 is very close to the frequency of a two photon exciton state, so that the output power of frequency ω 4 is resonantly enhanced by both of said exciton states.
Claim 3
Dependent Claim
16 words
An apparatus according to claim 1 in which said nonlinear interaction medium comprises a birefringent crystal.
Claim 4
Dependent Claim
27 words
An apparatus according to claim 2 in which said birefringent crystal is formed from elements in columns II and VI of the Periodic Table of the Elements.
Claim 5
Dependent Claim
16 words
An apparatus according to claim 3 in which said birefringent crystal is formed from cadmium sulphide.
References Cited (Backward Citations)
US4011462A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-12 | 1981-12-12 | 1982-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-12 | 1985-12-12 | 1986-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-12 | 1989-12-12 | 1990-06-13 | $7700.00 | Window Closed / Lapsed |