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US4795253A Expired / Lapsed US ⏱️ 0.0 years remaining

Remote sensing gas analyzer

Assignee: AIL Systems Inc
•
Filing: 1987-04-24
•
Granted: 1989-01-03
•
Expires: 2007-04-24
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Abstract

Abstract A particular area or areas are monitored for the presence of gaseous materials, particularly pollutants by collecting background radiation (both visible and infrared radiation) present in the selected area, analyzing the radiation collected with a spectrometer and making the results of this analysis available is a form understandable to the person or device moitoring the area for the presence of specified gaseous materials. The results of the spectrometric analysis may, for example, be displayed on a video unit or they may be printed. In a preferred embodiment, the results of the spectrometric analysis are displayed on a video unit simultaneously or sequentially with the image of the area from which the background radiation had been collected. Apparatus useful in the practice of this invention generally includes large energy collecting mirrors, an interferometer of the Michaelson-Morely type, a sensitive infrared detector, electronic data processing, and a device which records and/or displays the results of the determination(s). In a preferred apparatus, a "hot" mirror, a video camera, a computer and a video display unit are also employed.

Inventors

  • 👤 Robert L. Sandridge
  • 👤 Robert N. Hunt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 17:39
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/02; G01J3/0205; G01J3/0208; G01J3/28; G01J3/45; G01J3/453; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/35; G01N21/3504; G01N2021/1793; G01N2021/1795; G01N21/314; G01N2021/3155; G01N2021/3531

Claims Analysis

Total Claims: 45
Claim 1
Independent Claim 94 words
A process for detecting gaseous materials present in the atmosphere of a selected area comprising (a) collecting background radiation from the selected area, (b) analyzing the collected radiation having infrared wavelengths in a selected region with a spectrometer to detect any gaseous material present in the atmosphere which has a characteristic infrared spectrum in a selected wavelength region, (c) providing the results of the analysis of step (b) in a form understandable to a monitoring device or a human observer and (d) displaying as an image the visible radiation collected from the selected area.
Claim 2
Dependent Claim 94 words
A process for detecting gaseous materials present in the atmosphere of a selected area comprising (a) collecting background radiation from the selected area, (b) analyzing the collected radiation having infrared wavelengths in a selected region with a spectrometer to detect any gaseous material present in the atmosphere which has a characteristic infrared spectrum in a selected wavelength region, (c) providing the results of the analysis of step (b) in a form understandable to a monitoring device or a human observer and (d) displaying as an image the visible radiation collected from the selected area.
Claim 3
Dependent Claim 32 words
The process of claim 1 in which the background radiation collected in step (a) is separated into a portion composed of radiation having infrared wavelengths and a portion composed of visible radiation.
Claim 4
Dependent Claim 19 words
The process of claim 2 in which the selected region of infrared wavelengths is 3-5 μm and/or 8-14 μm.
Claim 5
Dependent Claim 18 words
The process of claim 3 in which the analysis is carried out with a Fourier Transform Infrared spectrometer.
Claim 6
Dependent Claim 25 words
The process of claim 4 in which the results of the infrared analysis of (b) are provided in accordance with (c) on a video screen.
Claim 7
Dependent Claim 26 words
The process of claim 5 in which the visible radiation is displayed in accordance with (d) simultaneously with the infrared analysis results on a video screen.
Claim 8
Dependent Claim 26 words
The process of claim 5 in which the visible radiation is displayed in accordance with (d) sequentially with the infrared analysis results on a video screen.
Claim 9
Dependent Claim 27 words
The process of claim 1 in which the spectrometer generates an interferogram in (b) which interferogram is processed by active electronic filters to improve the signal-to-noise ratio.
Claim 10
Dependent Claim 24 words
The process of claim I in which the results of the infrared analysis of (b) are provided on a video screen in step (c).
Claim 11
Dependent Claim 26 words
The process of claim 1 in which the infrared analysis of (b) and visible radiation image are displayed simultaneously or sequentially on a single video screen.
Claim 12
Dependent Claim 23 words
The process of claim 1 in which the infrared analysis of (b) and visible radiation image are displayed simultaneously on two video screens.
Claim 13
Dependent Claim 16 words
The process of claim 1 in which the selected region of infrared wavelengths is 3-5 μm.
Claim 14
Dependent Claim 36 words
The process of claim 1 in which visible radiation present in the selected area is collected by a video camera and background radiation including both infrared and visible radiation segments is collected by a reflective device.
Claim 15
Dependent Claim 28 words
The process of claim 13 in which the visible radiation collected by the video camera is collected prior to collection of the background radiation by a reflective device.
Claim 16
Dependent Claim 20 words
The process of claim 1 in which the background radiation from the selected area is collected from several different locations.
Claim 17
Dependent Claim 28 words
The process of claim 15 in which the results of the analyses of the infrared radiation are transmitted to a central data reduction device which correlates those results.
Claim 18
Dependent Claim 13 words
The process of claim 1 which is carried out on a continuous basis.
Claim 19
Dependent Claim 23 words
The process of claim 1 in which the area in which the gaseous materials are to be detected is changed at regular intervals.
Claim 20
Dependent Claim 24 words
The process of claim 1 in which the infrared analysis of (b) and visible radiation image are displayed sequentially on a single video screen.
Claim 21
Dependent Claim 16 words
The process of claim I in which the selected region of infrared wavelengths is 8-14 μm.
Claim 22
Dependent Claim 18 words
The process of claim 1 in which the selected region of infrared wavelength is 3-5 and 8-14 μm.
Claim 23
Independent Claim 74 words
An apparatus for monitoring the atmosphere of a selected area for the presence of gaseous materials comprising (a) a radiation collection device capable of collecting both infrared and visible radiation, (b) a video camera, (c) an interferometer capable of analyzing infrared radiation within a predetermined range of wavelengths collected by radiation collecting device (a) and (d) means for communicating the results of the interferometer analysis and a video image of the area being monitored.
Claim 24
Independent Claim 74 words
An apparatus for monitoring the atmosphere of a selected area for the presence of gaseous materials comprising (a) a radiation collection device capable of collecting both infrared and visible radiation, (b) a video camera, (c) an interferometer capable of analyzing infrared radiation within a predetermined range of wavelengths collected by radiation collecting device (a) and (d) means for communicating the results of the interferometer analysis and a video image of the area being monitored.
Claim 25
Dependent Claim 20 words
The apparatus of claim 22 in which the radiation collection device is a concave electroformed mirror with a rhodium surface.
Claim 26
Dependent Claim 101 words
The apparatus of claim 23 in which the interferometer (c) is composed of (1) a beamsplitter capable of splitting infrared radiation within a predetermined range of wavelengths positioned to receive the infrared radiation, (2) a first retroreflector positioned to receive radiation reflected by beamsplitter (1), (3) a second retroreflector positioned to receive radiation transmitted by beamsplitter (1), (4) a retroreflector support capable of moving retroreflector (2) or (3) in a reciprocating motion, (5) an off-axis paraboloid reflector positioned to receive combined infrared beams coming from the beamsplitter (1), and (6) an infrared detector positioned to receive infrared radiation from reflector (5).
Claim 27
Dependent Claim 37 words
The apparatus of claim 24 in which the retroreflector support is moved at a fixed reciprocating period such that a narrow band width interferogram containing information from the 3-5 μm or 8-14 μm infrared region is generated.
Claim 28
Dependent Claim 26 words
The apparatus of claim 25 in which the narrow band width interferogram is processed by active electronic filters to improve the signal-to-noise ratio of the interferogram.
Claim 29
Dependent Claim 23 words
The apparatus of claim 24 in which beamsplitter (3) is capable of splitting infrared radiation in the 3-5 μm and/or 8-14 μm range.
Claim 30
Dependent Claim 15 words
The apparatus of claim 27 in which retroreflectors (2) and (3) are corner cube retroreflectors.
Claim 31
Dependent Claim 14 words
The apparatus us of claim 27 in which infrared detector (6) is cryostatically cooled.
Claim 32
Dependent Claim 13 words
The apparatus of claim 27 in which the infrared detector is thermoelectrically cooled.
Claim 33
Dependent Claim 15 words
The apparatus of claim 24 in which retroreflectors (2) and (3) are corner cube retroreflectors.
Claim 34
Dependent Claim 19 words
The apparatus of claim 24 in which hot mirror is positioned between the radiation collection device and the interferometer.
Claim 35
Dependent Claim 20 words
The apparatus of claim 32 in which visible radiation transmitted through the hot mirror is received by a video camera.
Claim 36
Dependent Claim 28 words
The apparatus of claim 24 in which the video camera is positioned in front of radiation collection device (a) to collect visible radiation from the site being monitored.
Claim 37
Dependent Claim 28 words
The apparatus of claim 24 in which (d) is a computer programed to analyze an interferogram for the presence of one or more gaseous materials or concentration thereof.
Claim 38
Dependent Claim 25 words
The apparatus of claim 35 in which the computer is also programmed to control scanning of more than one preselected location on a continuous basis.
Claim 39
Dependent Claim 20 words
The apparatus of claim 22 in which a hot mirror is positioned between the radiation collection device and the interferometer.
Claim 40
Dependent Claim 20 words
The apparatus of claim 37 in which visible radiation transmitted through the hot mirror is received by a video camera.
Claim 41
Dependent Claim 25 words
The apparatus of claim 22 in which (d) is a computer programmed to analyze an interferogram for one or more gaseous materials and concentration thereof.
Claim 42
Dependent Claim 25 words
The apparatus of claim 39 in which the computer is also programmed to control scanning of more than one preselected location on a continuous basis.
Claim 43
Dependent Claim 22 words
The apparatus of claim 22 in which the video image and analysis of infrared radiation are simultaneously displayed on a viewing screen.
Claim 44
Dependent Claim 20 words
The apparatus of claim 22 in which the radiation collection device is a concave diamond-turned mirror with a rhodium surface.
Claim 45
Dependent Claim 22 words
The apparatus of claim 22 in which the video image and analysis of infrared radiation are sequentially displayed on a viewing screen.

References Cited (Backward Citations)

US3363525A Cited
US3766380A Cited
US3925666A Cited
US3931462A Cited
US4286877A Cited
US4490043A Cited
US4529317A Cited
US4650321A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-01-03 1992-07-04 1993-01-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-01-03 1996-07-04 1997-01-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-01-03 2000-07-04 2001-01-03 $7700.00 Window Closed / Lapsed

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