US4739269A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Orbit antenna for a nuclear magnetic resonance (NMR) imaging apparatus
Assignee: General Electric CGR SA
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Filing: 1987-01-05
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Granted: 1988-04-19
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Expires: 2007-01-05
Abstract
Abstract An orbit antenna for a nuclear magnetic resonance (NMR) imaging apparatus is symmetrized by joining together two concentric conductive loops in series. The antenna is frequency-tuned by a capacitor placed in parallel between the non-interconnected ends of the loops. A receiving circuit having a high input impedance is connected between the midpoint of the loops and one of the capacitor terminals. It is thus shown that the antenna is not unbalanced and endows the received signal with all the advantages of symmetrized antennas.
Inventors
- 👤 Jean P. Kopp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:34
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/32; G01R33/34; G01R33/34046; G01R33/34053; G01R33/341; G01R33/36; G01R33/3628; G01R33/3621
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
63 words
An orbit antenna for a nuclear magnetic resonance (NMR) imaging apparatus, wherein said antenna comprises: an even number of coaxial conductive loops in series having at least two non-interconnected ends, a tuning capacitor placed in parallel between the non-interconnected ends of said loops, a high input-impedance receiving circuit connected between the midpoint of the loops and one of the terminals of the capacitor.
Claim 2
Dependent Claim
63 words
An orbit antenna for a nuclear magnetic resonance (NMR) imaging apparatus, wherein said antenna comprises: an even number of coaxial conductive loops in series having at least two non-interconnected ends, a tuning capacitor placed in parallel between the non-interconnected ends of said loops, a high input-impedance receiving circuit connected between the midpoint of the loops and one of the terminals of the capacitor.
Claim 3
Dependent Claim
15 words
An antenna according to claim 1, wherein the even number has a value of 2.
Claim 4
Dependent Claim
49 words
An antenna according to claim 2, wherein the two loops are located in the same plane in intercrossed relation, each loop being constituted by an outer arc and an inner arc, the midpoint of the loops being at a location corresponding to the connection of the two inner arcs.
Claim 5
Dependent Claim
22 words
An antenna according to claim 2, wherein the loops are superposed and located in register on each side of a base plate.
Claim 6
Dependent Claim
19 words
An antenna according to claim 1, wherein the receiving circuit includes a field-effect transistor mounted with a common emitter.
Claim 7
Dependent Claim
50 words
An antenna according to claim 5, wherein current is supplied to the field-effect transistor from a supply circuit which is decoupled from the received signal via the central conductor of a coaxial cable constituting a high-frequency line for connecting the receiving circuit to a processing unit of the imaging apparatus.
References Cited (Backward Citations)
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US2999977A
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US2999978A
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US4528509A
Cited
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US4636730A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-19 | 1991-10-19 | 1992-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-19 | 1995-10-19 | 1996-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-19 | 1999-10-19 | 2000-04-19 | $7700.00 | Window Closed / Lapsed |