US4408162A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sensitivity NMR probe
Assignee: Varian Inc
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Filing: 1980-12-22
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Granted: 1983-10-04
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Expires: 2000-12-22
Abstract
Abstract In an NMR probe containing an observe coil and a decoupling coil, the signal-to-noise ratio of the observe channel is improved by inserting a back-to-back parallel combination of diodes in series with the decoupling coil to present an infinite impedance in the decoupling channel in its passive state for induced RF signals from the observe coil.
Inventors
- 👤 Herman Egger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:47
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/32; G01R33/36; G01R33/3642; G01R33/3657
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
72 words
An NMR spectrometer comprising: a probe; a receive channel further comprising a receive coil within said probe; a decoupler channel further comprising a decoupler coil within said probe and disposed in proximity to said receive coil, said decoupler connected in series with a pair of RF diodes, said diodes connected cathode-to-anode, whereby said decoupler circuit is an open circuit for sufficiently small signals coupled in said decoupler circuit from said receive coil.
Claim 2
Dependent Claim
72 words
An NMR spectrometer comprising: a probe; a receive channel further comprising a receive coil within said probe; a decoupler channel further comprising a decoupler coil within said probe and disposed in proximity to said receive coil, said decoupler connected in series with a pair of RF diodes, said diodes connected cathode-to-anode, whereby said decoupler circuit is an open circuit for sufficiently small signals coupled in said decoupler circuit from said receive coil.
Claim 3
Dependent Claim
35 words
The apparatus of claim 1 wherein said receive channel within said probe comprises a tuned circuit including said receive coil and said decoupler channel within said probe comprises a tuned circuit including said decoupler coil.
Claim 4
Dependent Claim
29 words
The apparatus of claim 2 wherein said rf diodes present substantially vanishing impedance to an rf signal supplied to said decoupler circuit from a source external to said probe.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-03 | 1987-04-04 | 1987-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-03 | 1991-04-04 | 1991-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-03 | 1995-04-04 | 1995-10-04 | $7700.00 | Window Closed / Lapsed |