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US4918698A
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Method of suppressing feedback oscillations in free electron lasers
Assignee: University of California
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Filing: 1989-02-24
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Granted: 1990-04-17
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Expires: 2009-02-24
Abstract
Abstract Feedback oscillations in a free electron laser are suppressed without significantly degrading the laser performance by means of an attenuator placed in a linear gain zone of its interaction region.
Inventors
- 👤 Joel Fajans
- 👤 Jonathan Wurtele
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:48
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/09; H01S3/0903
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
66 words
In a method of suppressing feedback oscillations in a free electron laser having an elongated waveguide, means for providing an electron beam propagating through said waveguide, means for superimposing microwave energy onto said electron beam, and means for providing a wiggler field to provide an interaction region inside said waveguide, the improvement wherein said method comprises placing an attenuator in said interaction region inside said waveguide.
Claim 2
Dependent Claim
66 words
In a method of suppressing feedback oscillations in a free electron laser having an elongated waveguide, means for providing an electron beam propagating through said waveguide, means for superimposing microwave energy onto said electron beam, and means for providing a wiggler field to provide an interaction region inside said waveguide, the improvement wherein said method comprises placing an attenuator in said interaction region inside said waveguide.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein said attenuator is substantially reflectionless.
Claim 4
Independent Claim
9 words
The method of claim wherein said attenuator comprises graphite.
Claim 5
Dependent Claim
15 words
The method of claim 1 wherein said attenuator comprises a dissipative but otherwise non-interacting matrix.
Claim 6
Dependent Claim
23 words
The method of claim 1 wherein said attenuator is placed at a position in said interaction region where the gain increases substantially linearly.
References Cited (Backward Citations)
US4845218A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-04-16 | 1993-10-16 | 1994-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-16 | 1997-10-16 | 1998-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-16 | 2001-10-16 | 2002-04-17 | $7700.00 | Window Closed / Lapsed |