US4757290A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hybrid resonator
Assignee: GE Medical Systems Israel Ltd
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Filing: 1987-02-06
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Granted: 1988-07-12
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Expires: 2007-02-06
Abstract
Abstract A circularly polarized radio frequency probe for use in magnetic resonance systems, the probe comprises four effective "saddle coils" arranged to define a single cylinder. The saddle coils each comprise a pair of 120 degree arcuate conductor sectors separated by longitudinal conductors. RF power is coupled to each of said "saddle coils" so that first and second pairs of said saddle coils generate first and second fields normal to each other.
Inventors
- 👤 Hannan Keren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:55
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/32; G01R33/36; G01R33/3678; G01R33/34; G01R33/34046
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
153 words
A hybrid resonator for use as a radio frequency probe in magnetic resonance (MR) systems, said systems having large static magnetic field extending in a longitudinal direction in a cylinder, said resonator comprising a pair of oppositely disposed spaced apart circular end coils, said end coils each being concentric about the same axis to thereby define a cylindrical shape, four longitudinal coils disposed between said circular end coils symetrically spaced apart around said cylindrical shape, each of said longitudinal coils comprising a pair of spaced apart longitudinal conductors, a pair of transverse conductors joining the longitudinal conductors at opposite ends thereof, said transverse conductors being adjacent and parallel to portions of said circular end coils, means for connecting each of said longitudinal coils to both of said circular end coils, capacitor means for tuning the hybrid resonator to the desired resonance frequency, and means for connecting radio frequency power to said hybrid resonator.
Claim 2
Dependent Claim
153 words
A hybrid resonator for use as a radio frequency probe in magnetic resonance (MR) systems, said systems having large static magnetic field extending in a longitudinal direction in a cylinder, said resonator comprising a pair of oppositely disposed spaced apart circular end coils, said end coils each being concentric about the same axis to thereby define a cylindrical shape, four longitudinal coils disposed between said circular end coils symetrically spaced apart around said cylindrical shape, each of said longitudinal coils comprising a pair of spaced apart longitudinal conductors, a pair of transverse conductors joining the longitudinal conductors at opposite ends thereof, said transverse conductors being adjacent and parallel to portions of said circular end coils, means for connecting each of said longitudinal coils to both of said circular end coils, capacitor means for tuning the hybrid resonator to the desired resonance frequency, and means for connecting radio frequency power to said hybrid resonator.
Claim 3
Dependent Claim
42 words
The hybrid resonator of claim 1 wherein said means for connecting each of said longitudinal coils to both of said circular end coils comprises means for connecting each of said transverse conductors at the midpoint thereof to said adjacent circular end coils.
Claim 4
Dependent Claim
28 words
The hybrid resonator of claim 2 wherein said capacitor means is located in the means for connecting each of said transverse conductors to said adjacent circular end coil.
Claim 5
Dependent Claim
67 words
The hybrid resonator of claim 3 wherein said means for connecting radio frequency power to said hybrid resonator comprises means for coupling a first RF source to one pair of oppositely disposed longitudinal coils and means for connecting a second RF source to the other pair of oppositely disposed longitudinal coils, and said first Rf source being 90 degrees out of phase with said second Rf source.
Claim 6
Dependent Claim
36 words
The hybrid resonator of claim 3 wherein said capacitor means comprises a matching capacitor in series with a tuning compacitor, and wherein said means for connecting power comprises connecting said Rf sources across said matching capacitors.
Claim 7
Dependent Claim
30 words
The hybrid resonator of claim 3 wherein said capacitor means comprises a matching capacitor and a tuning capacitor in series with the matching capacitor where said RF sources are connected.
Claim 8
Dependent Claim
37 words
The hybrid resonator of claim 3 wherein said capacitor means comprises only a tuning capacitor unless said Rf is connected thereto, said tuning capacitor being the means for connecting said longitudinal coils to said circular end coils.
Claim 9
Dependent Claim
30 words
The hybrid resonator of claim 1 wherein said longitudinal coils each extend over an arc of 60 degrees and are separated from each other by an arc of 30 degrees.
Claim 10
Dependent Claim
24 words
The hybrid resonator of claim 1 wherein the points of connecting said longitudinal coils to said circular end coils are separated by 90 degrees.
Claim 11
Dependent Claim
37 words
The hybrid resonator of claim 1 wherein said Rf sources are connected so that the current in said circular end coils is opposite in direction than the current in the adjacent transverse conductors of said longitudinal coils.
Claim 12
Dependent Claim
33 words
The hybrid resonator of claim 1 wherein said RF power is connected so that current in adjacent ones of said longitudinal conductors of different ones of said longitudinal coils run in opposite directions.
Claim 13
Dependent Claim
153 words
A hybrid resonator for use as a radio frequency (RF) coil in a magnetic resonance (MR), said system having a large static magnet extending in a longitudinal direction in a cylinder, said resonator comprising a pair of oppositely disposed spaced apart circular end coils, said end coils being concentric about the same axis to thereby define a cylindrical shape, four longitudinal coils disposed between said circular end coils symmetrically spaced apart around said cylindrical shape and arranged to provide in cooperation with said circular end coils saddle coils symmetrically spaced around said cylindrical shape, said longitudinal coils extending for 60 degrees, said saddle coils being comprised of longitudinal members of oppositely disposed ones of said longitudinal coils being separated by an arc of 120 degrees, and each of said saddle coils being oppositely disposed from another saddle coil and spaced apart from each other by the 60 degree extension of said longitudinal coils.
Claim 14
Dependent Claim
153 words
A hybrid resonator for use as a radio frequency (RF) coil in a magnetic resonance (MR), said system having a large static magnet extending in a longitudinal direction in a cylinder, said resonator comprising a pair of oppositely disposed spaced apart circular end coils, said end coils being concentric about the same axis to thereby define a cylindrical shape, four longitudinal coils disposed between said circular end coils symmetrically spaced apart around said cylindrical shape and arranged to provide in cooperation with said circular end coils saddle coils symmetrically spaced around said cylindrical shape, said longitudinal coils extending for 60 degrees, said saddle coils being comprised of longitudinal members of oppositely disposed ones of said longitudinal coils being separated by an arc of 120 degrees, and each of said saddle coils being oppositely disposed from another saddle coil and spaced apart from each other by the 60 degree extension of said longitudinal coils.
Claim 15
Dependent Claim
77 words
The hybrid resonator of claim 14 including means for tuning said hybrid resonator to the desired RF, means for connecting RF power to said hybrid resonator in a manner to electromagnetically isolate each of said pair of saddle coils from the other pair of saddle coils whereby each pair of saddle coils can be tuned to a different RF for activating a different element in an object being subjected to magnetic resonance diagnosis in the MR system.
References Cited (Backward Citations)
US4594566A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-12 | 1992-01-11 | 1992-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-12 | 1996-01-11 | 1996-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-12 | 2000-01-11 | 2000-07-12 | $7700.00 | Window Closed / Lapsed |