Patent US2168043A successfully refreshed from Google Patents.
Patent US3860880A successfully refreshed from Google Patents.
US3860880A
Expired / Lapsed
US
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Travelling wave optical amplifier and oscillator
Assignee: California Institute of Technology
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Filing: 1973-05-18
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Granted: 1975-01-14
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Expires: 1993-05-18
Abstract
Abstract A tunable travelling wave optical device consists of a dielectric optical waveguide with a top surface, which is periodically corrugated with a corrugation periodicity, L. At least the corrugated top surface is in an evacuated envelope wherein an electron beam with an adjustable electron velocity, ve is formed. The electron beam propagates in close proximity to and in a direction parallel to the direction of propagation of an optical beam through the guide. The electron velocity is adjusted to be greater than but on the order of the phase velocity of the first spatial harmonic generated in the corrugated waveguide. The wavelength lambda of the optical beam which is amplifiable by the device, or is produced therein when the latter acts as an oscillator, is substantially equal to c/ve L, c being the speed of light.
Inventors
- 👤 Amnon Yariv
- 👤 Desmond R Armstrong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:04
CPC Classifications
H; H01; H01J; H01J25/00; H01J25/34; H01J25/36; H01J25/38
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
164 words
A travelling wave optical amplifier comprising: a dielectric optical waveguide supportive of an optical beam of a wavelength lambda in the optical region, said waveguide having first and second opposite ends and a top surface extending between said ends, said top surface being characterized by periodic corrugations with a periodicity L, between said ends; an evacuated envelope containing therein at least said corrugated top surface of said waveguide; means in said envelope for providing a focused electron beam in said envelope with an electron velocity definable as ve, said electron beam being in close proximity to said corrugated top surface and extending in a direction parallel thereto; and input means for directing an optical beam of wavelength lambda to said waveguide which enters said waveguide through said first end, whereby said optical beam is amplified in said waveguide and the amplified optical beam exits said second end when lambda is not less and substantially equal to c/veL, where c is the speed of light.
Claim 2
Dependent Claim
164 words
A travelling wave optical amplifier comprising: a dielectric optical waveguide supportive of an optical beam of a wavelength lambda in the optical region, said waveguide having first and second opposite ends and a top surface extending between said ends, said top surface being characterized by periodic corrugations with a periodicity L, between said ends; an evacuated envelope containing therein at least said corrugated top surface of said waveguide; means in said envelope for providing a focused electron beam in said envelope with an electron velocity definable as ve, said electron beam being in close proximity to said corrugated top surface and extending in a direction parallel thereto; and input means for directing an optical beam of wavelength lambda to said waveguide which enters said waveguide through said first end, whereby said optical beam is amplified in said waveguide and the amplified optical beam exits said second end when lambda is not less and substantially equal to c/veL, where c is the speed of light.
Claim 3
Dependent Claim
38 words
The travelling wave optical amplifier as described in claim 1, wherein said electron velocity ve is adjustable by the means in said envelope which provide said focused electron beam, up to a value on the order of 1/10c.
Claim 4
Dependent Claim
17 words
The travelling wave optical amplifier as described in claim 2 wherein L is in the micron range.
Claim 5
Dependent Claim
50 words
The travelling wave optical amplifier as described in claim 1 wherein said electron beam is spaced apart from said corrugated top surface a distance which is less than lambda and whereat the amplitude of the spatial first harmonic generated in said waveguide by the corrugated surface is substantially a maximum.
Claim 6
Dependent Claim
38 words
The travelling wave optical amplifier as described in claim 1 wherein said amplifier further includes a thin transparent electroN-draining layer on top of said corrugated top surface for draining any electrons from said electron beam striking said layer.
Claim 7
Dependent Claim
58 words
The travelling wave optical amplifier as described in claim 5 wherein L is in the micron range and wherein said electron beam is spaced apart from said corrugated top surface a distance which is less than lambda and whereat the amplitude of the spatial first harmonic generated in said waveguide by the corrugated surface is substantially a maximum.
References Cited (Backward Citations)
US2866917A
Cited
US2939998A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-13 | 1978-07-15 | 1979-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-13 | 1982-07-15 | 1983-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-13 | 1986-07-15 | 1987-01-14 | $7700.00 | Window Closed / Lapsed |