US4661783A
Expired / Lapsed
US
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Free electron and cyclotron resonance distributed feedback lasers and masers
Assignee: United States Department of the Navy
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Filing: 1981-03-18
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Granted: 1987-04-28
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Expires: 2001-03-18
Abstract
Abstract Free-electron lasers and masers are modified by eliminating the resonator cavity as such. The feedback mechanism, essential to oscillation, is distributed through and integrated with the transmission line which guides the electromagnetic wave at the active region where interaction with the electron beam takes place. The feedback structure is created by perturbations in the transmission line along the length thereof at the locations of the zero electric field lines of a desired oscillatory standing wave mode. The perturbations may take the form of axial, helical, and azimuthal deformation of the transmission line.
Inventors
- 👤 Avraham Gover
- 👤 Michael E. Read
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:50
CPC Classifications
H; H01; H01S; H01S3/00; H01S3/09; H01S3/0903; H01J; H01J25/00; H01J25/02; H01J25/025
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
114 words
In an electromagnetic wave gyrotron oscillator of the type which produces radiation by direct conversion of the kinetic energy of an electron beam to radiative energy, the oscillator including an active region where an interaction between the electron beam and an electromagnetic wave takes place and a transmission line for guiding the electromagnetic wave at the active region, means for perturbing the transmission characteristics of the transmission line along the zero electric field lines of a wave mode at which the oscillator is desired to operate, to provide a high Q factor to the desired wave mode and a low Q factor to other wave modes which may compete with the desired wave mode.
Claim 2
Dependent Claim
114 words
In an electromagnetic wave gyrotron oscillator of the type which produces radiation by direct conversion of the kinetic energy of an electron beam to radiative energy, the oscillator including an active region where an interaction between the electron beam and an electromagnetic wave takes place and a transmission line for guiding the electromagnetic wave at the active region, means for perturbing the transmission characteristics of the transmission line along the zero electric field lines of a wave mode at which the oscillator is desired to operate, to provide a high Q factor to the desired wave mode and a low Q factor to other wave modes which may compete with the desired wave mode.
Claim 3
Dependent Claim
70 words
The oscillator recited in claim 1 wherein the perturbing means includes: an azimuthal deformation of the transmission line, the azimuthal deformation having an axial coordinate z satisfying the relation z=L.sub.n where L n =n(λ z /2), n is an integer, λ z is the axial wavelength of the wave mode at which the oscillator is desired to operate, and z is measured from the input plane of the transmission line.
Claim 4
Dependent Claim
49 words
The oscillator recited in claim 1 wherein the perturbing means includes: a plurality of elements periodically spaced apart in the axial direction of the transmission line by λ z /2 where λ z is the axial wavelength of the wave mode at which the oscillator is desired to operate.
Claim 5
Dependent Claim
43 words
The oscillator recited in claim 1 wherein the perturbing means includes: an axial deformation of the transmission line, the axial deformation having an azimuthal coordinate satisfying the relation φ=mπ/n where n is an integer, and m=0, 1, 2, . . . , 2n-1.
Claim 6
Dependent Claim
15 words
The oscillator recited in claim 1 wherein: the perturbing means extends outside the active region.
Claim 7
Dependent Claim
13 words
The oscillator recited in claim 1 wherein transmission line includes: a coaxial line.
Claim 8
Dependent Claim
21 words
The oscillator recited in claim 6 wherein the perturbing means includes: a corrugation of the center conductor of the coaxial line.
Claim 9
Dependent Claim
23 words
The oscillator recited in claim 6 wherein the perturbing means includes: highly conductive fins disposed on the center conductor of the coaxial line.
Claim 10
Dependent Claim
22 words
The oscillator recited in claim 6 wherein the perturbing means includes: lossy material disposed on the center conductor of the coaxial line.
Claim 11
Dependent Claim
116 words
In an electromagnetic wave cyclotron resonance maser oscillator of the type which produces radiation by direct conversion of the kinetic energy of an electron beam to radiative energy, the oscillator including an active region where an interaction between the electron beam and an electromagnetic wave takes place and a transmission line for guiding the electromagnetic wave at the active region, means for perturbing the transmission characteristics of the transmission line along the zero electric field lines of a wave mode at which the oscillator is desired to operate, to provide a high Q factor to the desired wave mode and a low Q factor to other wave modes which may compete with the desired wave mode.
Claim 12
Dependent Claim
116 words
In an electromagnetic wave cyclotron resonance maser oscillator of the type which produces radiation by direct conversion of the kinetic energy of an electron beam to radiative energy, the oscillator including an active region where an interaction between the electron beam and an electromagnetic wave takes place and a transmission line for guiding the electromagnetic wave at the active region, means for perturbing the transmission characteristics of the transmission line along the zero electric field lines of a wave mode at which the oscillator is desired to operate, to provide a high Q factor to the desired wave mode and a low Q factor to other wave modes which may compete with the desired wave mode.
Claim 13
Dependent Claim
116 words
In an electromagnetic wave magnetic bremsstrahlung laser oscillator of the type which produces radiation by direct conversion of the kinetic energy of an electron beam to radiative energy, the oscillator including an active region where an interaction between the electron beam and an electromagnetic wave takes place and a transmission line for guiding the electromagnetic wave at the active region, means for perturbing the transmission characteristics of the transmission line along the zero electric field lines of a wave mode at which the oscillator is desired to operate, to provide a high Q factor to the desired wave mode and a low Q factor to other wave modes which may compete with the desired wave mode.
Claim 14
Dependent Claim
116 words
In an electromagnetic wave magnetic bremsstrahlung laser oscillator of the type which produces radiation by direct conversion of the kinetic energy of an electron beam to radiative energy, the oscillator including an active region where an interaction between the electron beam and an electromagnetic wave takes place and a transmission line for guiding the electromagnetic wave at the active region, means for perturbing the transmission characteristics of the transmission line along the zero electric field lines of a wave mode at which the oscillator is desired to operate, to provide a high Q factor to the desired wave mode and a low Q factor to other wave modes which may compete with the desired wave mode.
References Cited (Backward Citations)
US3398376A
Cited
US3760292A
Cited
US3822410A
Cited
US3868589A
Cited
US3786368A
Cited
US3970959A
Cited
US3884549A
Cited
US3906393A
Cited
US3898585A
Cited
US3970958A
Cited
US3958188A
Cited
US3972008A
Cited
US4096446A
Cited
US4345329A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-27 | 1990-10-27 | 1991-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-27 | 1994-10-27 | 1995-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-27 | 1998-10-27 | 1999-04-28 | $7700.00 | Window Closed / Lapsed |