US4751465A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spurious resonance control for NMR observe coils
Assignee: Varian Inc
•
Filing: 1987-04-30
•
Granted: 1988-06-14
•
Expires: 2007-04-30
Abstract
Abstract The tuned LC circuit of an NMR probe includes a coil center tapped to ground through a capacitance selected to constrain parasitic resonances to a frequency region below decoupler frequencies employed in the probe.
Inventors
- 👤 Albert P. Zens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:19
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/32; G01R33/36; G01R33/3628
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
96 words
An NMR probe including a balanced parallel resonant LC circuit for detecting induced signals relative to a common potential, comprising: a coil and first capacitor forming said parallel tuned circuit; each junction of said coil and first capacitor connected respectively to second and third capacitors, said third capacitor in turn connected to said common potential, and said second capacitor adapted for connection to derive a signal therefrom; a fourth capacitance connected from substantially the center of said coil to said common potential whereby parasitic resonance may be constrained to a frequency below an upper limit frequency.
Claim 2
Dependent Claim
96 words
An NMR probe including a balanced parallel resonant LC circuit for detecting induced signals relative to a common potential, comprising: a coil and first capacitor forming said parallel tuned circuit; each junction of said coil and first capacitor connected respectively to second and third capacitors, said third capacitor in turn connected to said common potential, and said second capacitor adapted for connection to derive a signal therefrom; a fourth capacitance connected from substantially the center of said coil to said common potential whereby parasitic resonance may be constrained to a frequency below an upper limit frequency.
Claim 3
Dependent Claim
111 words
A probe including a parallel resonant LC circuit for detecting induced signals relative to a common potential comprising a coil and first capacitor each having two terminals forming said parallel tuned circuit, one junction comprising one terminal of said coil and first capacitor connected respectively to a second capacitor, the other terminal of said coil connected to said common potential, said first capacitor in turn connected to said common potential, and said second capacitor adapted for connection to derive a signal therefrom, a third capacitance connected from substantially the center of said coil to said common potential whereby parasitic resonance may be constrained to a frequency below an upper limit frequency.
Claim 4
Dependent Claim
111 words
A probe including a parallel resonant LC circuit for detecting induced signals relative to a common potential comprising a coil and first capacitor each having two terminals forming said parallel tuned circuit, one junction comprising one terminal of said coil and first capacitor connected respectively to a second capacitor, the other terminal of said coil connected to said common potential, said first capacitor in turn connected to said common potential, and said second capacitor adapted for connection to derive a signal therefrom, a third capacitance connected from substantially the center of said coil to said common potential whereby parasitic resonance may be constrained to a frequency below an upper limit frequency.
Claim 5
Dependent Claim
112 words
A probe including a parallel resonant LC circuit for detecting induced signals relative to a common potential comprising a coil and first capacitor each having two terminals forming said parallel tuned circuit, one junction of one terminal of said coil and first capacitor connected respectively to a second capacitor, the other terminal of said coil connected to said common potential, said first capacitor in turn connected to said common potential, and said second capacitor adapted for connection to derive a signal therefrom, a dc conductive link connected from substantially the center of said coil to said common potential whereby parasitic resonance may be constrained to a frequency below an upper limit frequency.
Claim 6
Dependent Claim
112 words
A probe including a parallel resonant LC circuit for detecting induced signals relative to a common potential comprising a coil and first capacitor each having two terminals forming said parallel tuned circuit, one junction of one terminal of said coil and first capacitor connected respectively to a second capacitor, the other terminal of said coil connected to said common potential, said first capacitor in turn connected to said common potential, and said second capacitor adapted for connection to derive a signal therefrom, a dc conductive link connected from substantially the center of said coil to said common potential whereby parasitic resonance may be constrained to a frequency below an upper limit frequency.
References Cited (Backward Citations)
US3281680A
Cited
US3242424A
Cited
US3529234A
Cited
US3771055A
Cited
US4075552A
Cited
US4129822A
Cited
US4295092A
Cited
US4450408A
Cited
US4621237A
Cited
US4633181A
Cited
US4682125A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-06-14 | 1991-12-14 | 1992-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-14 | 1995-12-14 | 1996-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-14 | 1999-12-14 | 2000-06-14 | $7700.00 | Window Closed / Lapsed |