Patent US3788742A successfully refreshed from Google Patents.
US3788742A
Expired / Lapsed
US
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Gas monitoring system
Assignee: Westinghouse Electric Corp
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Filing: 1971-06-24
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Granted: 1974-01-29
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Expires: 1991-06-24
Abstract
Abstract A monochromatic laser beam tuned to a wavelength which coincides with one of the natural absorption lines of the gas molecular species to be detected is directed towards the gas medium being monitored. A remotely located receiver positioned in proximity to or near the laser system, views the radiated region of the monitored gas in two spectral regions; one in the absorption band and the other on either side of the absorption band. The receiver develops signals from the backscattered irradiation in the time and frequency domain to determine the presence and measure the density, depth and range of the molecular species being detected in the illuminated cross section of the monitored gas. A second method employed by this invention utilizes the polarization characteristics of the backscattered radiation, incurred from processes such as resonant imprisonment in the monitored gas, to determine the presence of the molecular species being detected.
Inventors
- 👤 M Garbuny
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:38
CPC Classifications
G; G01; G01S; G01S17/00; G01S17/02; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/39; G01N33/00; G01N33/0004; G01N33/0009; G01N33/0027
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
137 words
The method of remotely monitoring a gas distribution comprising the steps of: exclusively irradiating the gas distribution with monochromatic laser radiation of a wavelength which substantially coincides with one of the natural absorption lines of at least one gas molecular species to be detected to optimize the process of resonance imprisonment occurring within the distribution; positioning a receiver substantially proximate to said laser to view the backscattered radiation from the irradiated region of the gas distribution; converting the signal viewed by said receiver into a frequency spectrum; taking the ratio of the amplitude of the spectral lines in said spectrum with frequencies in the wings of the central spectral line to that in a narrow interval around the laser frequency; and correlating said ratio as a measure of the gaseous density of the gas molecular species detected.
Claim 2
Independent Claim
137 words
The method of remotely monitoring a gas distribution comprising the steps of: exclusively irradiating the gas distribution with monochromatic laser radiation of a wavelength which substantially coincides with one of the natural absorption lines of at least one gas molecular species to be detected to optimize the process of resonance imprisonment occurring within the distribution; positioning a receiver substantially proximate to said laser to view the backscattered radiation from the irradiated region of the gas distribution; converting the signal viewed by said receiver into a frequency spectrum; taking the ratio of the amplitude of the spectral lines in said spectrum with frequencies in the wings of the central spectral line to that in a narrow interval around the laser frequency; and correlating said ratio as a measure of the gaseous density of the gas molecular species detected.
Claim 3
Dependent Claim
31 words
The method of claim 1 wherein said correlating step comprises comparing said ratio to a known standard to determine a measure of the gaseous density of the gas molecular species detected.
Claim 4
Dependent Claim
50 words
The method of claim 1 including the steps of: detecting signals in said receiver as a function of time; measuring the delay between the transmission of said laser radiation and the receivers encounter of the backscattered radiation; and calculating the range of the detected gaseous molecular species from said delay.
Claim 5
Dependent Claim
37 words
The method of claim 3 wherein said correlating step comprises coMparing said time signal to said ratio to determine the molecular density and depth along the axis of incident laser radiation of the gas molecular species detected.
Claim 6
Independent Claim
151 words
The method of remotely monitoring a gas distribution comprising the steps of: exclusively irradiating the gas distribution with monochromatic laser radiation of a wavelength which substantially coincides with one of the natural absorption lines of at least one gas molecular species to be detected to optimize the process of resonance imprisonment occurring within the distribution; positioning a receiver substantially proximate to said laser to view the backscattered radiation from the irradiated region of the gas distribution; converting the signal viewed by said receiver into a frequency spectrum; detuning the laser radiation around the natural absorption line of the detected gas molecular species to a wavelength that reduces the received signal to a set fraction of the incident laser radiation; and correlating said detuned wavelength to determine the presence of the detected molecular species within the monitored gas distribution and as a measure of the gaseous density of the detected molecular species.
Claim 7
Independent Claim
151 words
The method of remotely monitoring a gas distribution comprising the steps of: exclusively irradiating the gas distribution with monochromatic laser radiation of a wavelength which substantially coincides with one of the natural absorption lines of at least one gas molecular species to be detected to optimize the process of resonance imprisonment occurring within the distribution; positioning a receiver substantially proximate to said laser to view the backscattered radiation from the irradiated region of the gas distribution; converting the signal viewed by said receiver into a frequency spectrum; detuning the laser radiation around the natural absorption line of the detected gas molecular species to a wavelength that reduces the received signal to a set fraction of the incident laser radiation; and correlating said detuned wavelength to determine the presence of the detected molecular species within the monitored gas distribution and as a measure of the gaseous density of the detected molecular species.
Claim 8
Dependent Claim
44 words
The method of claim 5 wherein said correlating step comprises: taking the difference between the natural absorption wavelength and said detuned wavelength; and comparing said difference with a known standard to determine a measure of the gaseous density of the gas molecular species detected.
Claim 9
Dependent Claim
50 words
The method of claim 5 including the steps of: detecting signals in said receiver as a function of time; measuring the delay between the transmission of said laser radiation and the receivers encounter of the backscattered radiation; and calculating the range of the detected gaseous molecular species from said delay.
Claim 10
Dependent Claim
38 words
The method of claim 7 wherein said correlating step comprises comparing said time signal to said detuned wavelength to determine the molecular density and depth along the axis of incident laser radiation of the detected gas molecular species.
Claim 11
Independent Claim
175 words
The method of remotely monitoring a gas distribution comprising the steps of: exclusively irradiating the gas distribution with monochromatic laser radiation of a wavelength which substantially coincides with one of the natural absorption lines of at least one gas molecular species to be detected to optimize the process of resonance imprisonment occurring within the distribution; positioning a receiver substantially proximate to said laser to view the backscattered radiation from the irradiated region of the gas distribution; detecting signals in said receiver as a function of time; determining from said time signal the presence of the detected gas molecular species within the monitored gas distribution; converting the signal from the receiver into a frequency spectrum; taking a ratio of the amplitude of the spectral lines in said spectrum with frequencies in the wings of the central spectral line to that in a narrow interval around the laser frequency; and correlating said time signal to said ratio to determine the molecular density and depth along the axis of incident laser radiation of the gas molecular species detected.
Claim 12
Independent Claim
175 words
The method of remotely monitoring a gas distribution comprising the steps of: exclusively irradiating the gas distribution with monochromatic laser radiation of a wavelength which substantially coincides with one of the natural absorption lines of at least one gas molecular species to be detected to optimize the process of resonance imprisonment occurring within the distribution; positioning a receiver substantially proximate to said laser to view the backscattered radiation from the irradiated region of the gas distribution; detecting signals in said receiver as a function of time; determining from said time signal the presence of the detected gas molecular species within the monitored gas distribution; converting the signal from the receiver into a frequency spectrum; taking a ratio of the amplitude of the spectral lines in said spectrum with frequencies in the wings of the central spectral line to that in a narrow interval around the laser frequency; and correlating said time signal to said ratio to determine the molecular density and depth along the axis of incident laser radiation of the gas molecular species detected.
Claim 13
Independent Claim
174 words
The method of remotely monitoring a gas distribution comprising the steps of: exclusively irradiating the gas distribution with monochromatic laser radiation of a wavelength which substantially coincides with one of the natural absorption lines of at least one gas molecular species to be detected to optimize the process of resonance imprisonment occurring within the distribution; positioning a receiver substantially proximate to said laser to view the backscattered radiation from the irradiated region of the gas distribution; detecting signals in said receiver as a function of time; determining from said time signal the presence of the detected molecular species within the monitored gas distributioN; converting the signal from the receiver into a frequency spectrum; detuning the laser radiation around the natural absorption line of the detected gas molecular species to a wavelength that reduces the received signal to a set fraction of the incident laser radiation; and correlating said time signal to said detuned wqvelength to determine the molecular density and depth along the axis of incident laser radiation of the gas molecular species detected.
Claim 14
Independent Claim
174 words
The method of remotely monitoring a gas distribution comprising the steps of: exclusively irradiating the gas distribution with monochromatic laser radiation of a wavelength which substantially coincides with one of the natural absorption lines of at least one gas molecular species to be detected to optimize the process of resonance imprisonment occurring within the distribution; positioning a receiver substantially proximate to said laser to view the backscattered radiation from the irradiated region of the gas distribution; detecting signals in said receiver as a function of time; determining from said time signal the presence of the detected molecular species within the monitored gas distributioN; converting the signal from the receiver into a frequency spectrum; detuning the laser radiation around the natural absorption line of the detected gas molecular species to a wavelength that reduces the received signal to a set fraction of the incident laser radiation; and correlating said time signal to said detuned wqvelength to determine the molecular density and depth along the axis of incident laser radiation of the gas molecular species detected.
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) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |