US3781650A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for reducing interference in a spin resonance spectrometer by subtracting interferograms having 180 grad phase separation
Assignee: Spectrospin AG
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Filing: 1972-05-09
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Granted: 1973-12-25
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Expires: 1992-05-09
Abstract
Abstract A method and apparatus are described for reducing interference in the receiver of a spin resonance spectrometer. The apparatus generates a first set of RF excitation pulses of one phase angle and a second set of RF pulses having a phase angle that is 180* different. The interferograms formed by one set of these pulses are then subtracted from those formed by the other in a signal averager.
Inventors
- 👤 T Keller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 07:57
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/44; G01R33/46; G01R33/4625
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
97 words
A method for recording spin resonance spectra, comprising: exciting a spin system of a sample with a first set of RF pulses having a first phase angle and a second set of RF pulses having a second phase angle that is 180* different from the first phase angle; receiving interferograms containing the resonance frequencies of the spin system excited by the first and second sets of pulses; and subtracting an interferogram formed by one of the first and second sets of RF pulses from an interferogram formed by the oTher set to obtain a mean value thereof.
Claim 2
Independent Claim
97 words
A method for recording spin resonance spectra, comprising: exciting a spin system of a sample with a first set of RF pulses having a first phase angle and a second set of RF pulses having a second phase angle that is 180* different from the first phase angle; receiving interferograms containing the resonance frequencies of the spin system excited by the first and second sets of pulses; and subtracting an interferogram formed by one of the first and second sets of RF pulses from an interferogram formed by the oTher set to obtain a mean value thereof.
Claim 3
Dependent Claim
21 words
The method of claim 1 wherein the pulses of the first and second sets of RF pulses alternate with each other.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein the phase of each pulse is determined stochastically.
Claim 5
Dependent Claim
20 words
The method of claim 3 wherein the first and second sets of RF pulses have approximately equal numbers of pulses.
Claim 6
Dependent Claim
27 words
The method of claim 1 including the step of generating the first and second RF pulses by modulating an RF signal with modulation pulses of alternating polarity.
Claim 7
Dependent Claim
23 words
The method of claim 1 further comprising the step of Fourier analyzing the mean value interferogram to determine the component resonance frequencies thereof.
Claim 8
Dependent Claim
96 words
Apparatus for recording spin resonance spectra comprising: a spin resonance spectrometer including an RF oscillator, a pulse generator, an RF modulator for pulse modulating the output of the RF oscillator, and a signal averager for averaging interferograms produced in response to each excitation pulse to obtain the mean value thereof; means in said pulse generator for forming pulses of opposite polarity; means for applying said pulses of opposite polarity to the RF modulator; and means for applying corresponding pulses of opposite polarity to the signal averager for controlling the sign of the addition operation performed thereby.
Claim 9
Dependent Claim
96 words
Apparatus for recording spin resonance spectra comprising: a spin resonance spectrometer including an RF oscillator, a pulse generator, an RF modulator for pulse modulating the output of the RF oscillator, and a signal averager for averaging interferograms produced in response to each excitation pulse to obtain the mean value thereof; means in said pulse generator for forming pulses of opposite polarity; means for applying said pulses of opposite polarity to the RF modulator; and means for applying corresponding pulses of opposite polarity to the signal averager for controlling the sign of the addition operation performed thereby.
Claim 10
Dependent Claim
18 words
The apparatus of claim 7 including means for forming pulses of opposite polarity that alternate with each other.
Claim 11
Dependent Claim
15 words
The apparatus of claim 7 including means for forming pulses having stochastically determined phase angles.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |