US5814987A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for and method of nuclear resonance testing
Assignee: CLEARWATER HOLDINGS NO 1 PTY Ltd
•
Filing: 1994-09-23
•
Granted: 1998-09-29
•
Expires: 2014-09-23
Abstract
Abstract Apparatus for Nuclear Quadrupole Resonance testing a sample comprises: means for applying excitation to the sample to excite NQR resonance, the excitation comprising at least one excitation pulse, the or each pulse covering a selected excitation frequency range, for the or each pulse the phase of the excitation varying generally non-linearly with the excitation frequency over the selected range; and means for detecting the NQR response signal.
Inventors
- 👤 John Alec Sydney Smith
- 👤 Martin Blanz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:32
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01R33/446; G01R33/441
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
94 words
Apparatus for Nuclear Quadrupole Resonance (NQR) testing a sample, comprising: means for applying excitation to the sample; means for detecting the response signal; and control means adapted to control the excitation applying means to apply excitation to the sample to excite NQR resonance, the excitation comprising at least one excitation pulse, each excitation pulse covering a selected excitation frequency range, the phase of each excitation pulse varying generally non-linearly with the excitation frequency over the selected range, the control means further being adapted to control the detecting means to detect the NQR response signal.
Claim 2
Dependent Claim
94 words
Apparatus for Nuclear Quadrupole Resonance (NQR) testing a sample, comprising: means for applying excitation to the sample; means for detecting the response signal; and control means adapted to control the excitation applying means to apply excitation to the sample to excite NQR resonance, the excitation comprising at least one excitation pulse, each excitation pulse covering a selected excitation frequency range, the phase of each excitation pulse varying generally non-linearly with the excitation frequency over the selected range, the control means further being adapted to control the detecting means to detect the NQR response signal.
Claim 3
Dependent Claim
24 words
Apparatus according to claim 1 wherein for the duration of the excitation an envelope of the time domain excitation waveform has no zero crossing.
Claim 4
Dependent Claim
27 words
Apparatus according to claim 1 wherein the excitation applying means is adapted to apply excitation the time domain waveform of which is both amplitude and phase modulated.
Claim 5
Dependent Claim
33 words
Apparatus according to claim 3 wherein the applying means includes means for producing two signals which are in relative quadrature, and means for combining the signals toform the amplitude and phase modulated excitation.
Claim 6
Dependent Claim
28 words
Apparatus according to claim 1 wherein the applying means is adapted to apply excitation the time domain waveform of which is amplitude modulated but not otherwise phase modulated.
Claim 7
Dependent Claim
27 words
Apparatus according to claim 1 wherein the applying means is adapted to apply excitation the time domain waveform of which is modulated according to a chirp function.
Claim 8
Dependent Claim
42 words
Apparatus according to claim 1 wherein the excitation applying means includes means for generating a carrier signal and means for modulating the carrier signal to produce excitation the phase of which varies generally non-linearly with the excitation frequency over the selected range.
Claim 9
Dependent Claim
24 words
Apparatus according to claim 7 wherein the modulating means includes means for storing a representation of a modulating waveform for modulating the carrier signal.
Claim 10
Dependent Claim
18 words
Apparatus according to claim 1 wherein the phase of the excitation varies generally quadratically with a frequency off-set.
Claim 11
Dependent Claim
32 words
Apparatus according to claim 1 wherein the excitation applying means is adapted to apply a plurality of excitation pulses, in such a way as to generate at least one echo response signal.
Claim 12
Dependent Claim
23 words
Apparatus according to claim 1 wherein the modulus of the frequency domain excitation spectrum is substantially constant over the selected excitation frequency range.
Claim 13
Dependent Claim
30 words
Apparatus according to claim 1, being for the detection of the presence of a given NQR substance in the sample, including an alarm for indicating the presence of the substance.
Claim 14
Independent Claim
60 words
A method of Nuclear Quadrupole Resonance (NQR) testing a sample, comprising: applying excitation to the sample to excite NQR resonance, the excitation comprising at least one excitation pulse, each excitation pulse covering a selected excitation frequency range, the phase of each excitation pulse varying generally non-linearly with the excitation frequency over the selected range; and detecting the NQR response signal.
Claim 15
Independent Claim
60 words
A method of Nuclear Quadrupole Resonance (NQR) testing a sample, comprising: applying excitation to the sample to excite NQR resonance, the excitation comprising at least one excitation pulse, each excitation pulse covering a selected excitation frequency range, the phase of each excitation pulse varying generally non-linearly with the excitation frequency over the selected range; and detecting the NQR response signal.
Claim 16
Dependent Claim
25 words
A method according to claim 13 wherein for the duration of the excitation an envelope of the time domain excitation waveform has no zero crossing.
Claim 17
Dependent Claim
20 words
A method according to claim 13 wherein the time domain waveform of the excitation is both phase and amplitude modulated.
Claim 18
Dependent Claim
22 words
A method according to claim 13 wherein the time domain waveform of the excitation is amplitude modulated but not otherwise phase modulated.
Claim 19
Dependent Claim
21 words
A method according to claim 13 wherein the time domain waveform of the excitation is modulated according to a chirp function.
Claim 20
Dependent Claim
21 words
A method according to claim 13 wherein the variation of the phase of the excitation with the excitation frequency is symmetric.
Claim 21
Dependent Claim
21 words
A method according to claim 13 wherein the variation of the phase of the excitation with the excitation frequency is antisymmetric.
Claim 22
Dependent Claim
19 words
A method according to claim 13 wherein the phase of the excitation varies generally quadratically with a frequency off-set.
Claim 23
Dependent Claim
27 words
A method according to claim 13 wherein a plurality of excitation pulses are applied, in such a way as to generate at least one echo response signal.
Claim 24
Dependent Claim
42 words
A method according to claim 13 wherein a selected NQR resonance is excited with at least one excitation pulse, and the duration of the excitation pulse is less than twice the free induction decay time, T 2 *, appropriate to that resonance.
Claim 25
Dependent Claim
17 words
A method according to claim 22 wherein the duration is less than 100% of T 2 *.
Claim 26
Dependent Claim
21 words
A method according to claim 13, being for the detection of the presence of a given NQR substance in the sample.
Claim 27
Dependent Claim
17 words
A method according to claim 24 wherein the presence of the substance is indicated by an alarm.
Claim 28
Dependent Claim
13 words
A method according to claim 13 wherein the sample comprises a polycrystalline substance.
Claim 29
Independent Claim
54 words
A method of extending the Nuclear Quadrupole Resonance (NQR) free induction decay time, T 2 *, of a sample containing quadrupolar nuclei, comprising applying excitation to the sample over a selected excitation frequency range to excite NQR resonance, the phase of the excitation varying generally non-linearly with the excitation frequency over the selected range.
Claim 30
Independent Claim
54 words
A method of extending the Nuclear Quadrupole Resonance (NQR) free induction decay time, T 2 *, of a sample containing quadrupolar nuclei, comprising applying excitation to the sample over a selected excitation frequency range to excite NQR resonance, the phase of the excitation varying generally non-linearly with the excitation frequency over the selected range.
References Cited (Backward Citations)
US3643181A
Cited
GB1357686A
Cited
US3768003A
Cited
GB1448939A
Cited
US3968424A
Cited
US4034191A
Cited
EP0209374A2
Cited
US4703267A
Cited
EP0242911A1
Cited
US4766380A
Cited
US4906932A
Cited
GB2206970A
Cited
GB2208442A
Cited
US5153515A
Cited
EP0394504A1
Cited
WO1991015754A1
Cited
GB2255830A
Cited
GB2254923A
Cited
WO1992017794A1
Cited
US5583437A
Cited
GB2255414A
Cited
US5500591A
Cited
US5233300A
Cited
WO1992021989A2
Cited
WO1993002365A1
Cited
US5365171A
Cited
EP0601229A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-09-28 | 2002-03-30 | 2002-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-09-28 | 2006-03-30 | 2006-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-09-28 | 2010-03-30 | 2010-09-29 | $7700.00 | Window Closed / Lapsed |