US4627284A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultraviolet absorption hygrometer
Assignee: SPECTRAL SCIENCES Inc A CORP OF MASSACHUSETTS
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Filing: 1985-07-22
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Granted: 1986-12-09
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Expires: 2005-07-22
Abstract
Abstract An ultraviolet absorption hygrometer is provided including a source of pulsed ultraviolet radiation for providing radiation in a first wavelength region where water absorbs significantly and in a second proximate wavelength region where water absorbs weakly. Ultraviolet radiation in the first and second regions which has been transmitted through a sample path of atmosphere is detected. The intensity of the radiation transmitted in each of the first and second regions is compared and from this comparison the amount of water in the sample path is determined.
Inventors
- 👤 Michael E. Gersh
- 👤 Fritz Bien
- 👤 Lawrence S. Bernstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 11:15
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/33; G01W; G01W1/00; G01J; G01J1/00; G01J1/10; G01J1/16; G01J1/1626; G01N21/314; G01N2201/00; G01N2201/06; G01N2201/069; G01N2201/0696; G01N2201/08; G01N2201/0806
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
99 words
An ultraviolet absorption hygrometer comprising: a source of pulsed ultraviolet radiation for providing in each pulse radiation both in a first wavelength region where water absorbs significantly, and in a second proximate wavelength region where water absorbs weakly; means for detecting ultraviolet radiation respectively in said first and second regions transmitted through a single sample path of gas; means, responsive to said means for detecting, for comparing the intensity of the radiation transmitted in each of the first and second regions; and means, responsive to said means for comparing, for determining the amount of water in the sample path.
Claim 2
Dependent Claim
99 words
An ultraviolet absorption hygrometer comprising: a source of pulsed ultraviolet radiation for providing in each pulse radiation both in a first wavelength region where water absorbs significantly, and in a second proximate wavelength region where water absorbs weakly; means for detecting ultraviolet radiation respectively in said first and second regions transmitted through a single sample path of gas; means, responsive to said means for detecting, for comparing the intensity of the radiation transmitted in each of the first and second regions; and means, responsive to said means for comparing, for determining the amount of water in the sample path.
Claim 3
Dependent Claim
19 words
The hygrometer of claim 1 in which said first and second wavelength regions are between 1700 and 2100 Angstroms.
Claim 4
Dependent Claim
23 words
The hygrometer of claim 1 further including a strobe circuit for periodically energizing and de-energizing said source to provide the pulsed ultraviolet radiation.
Claim 5
Dependent Claim
37 words
The hygrometer of claim 1 in which said means for detecting includes a first filter for transmitting only radiation in said first wavelength region and a second filter for transmitting only radiation in said second wavelength region.
Claim 6
Dependent Claim
30 words
The hygrometer of claim 4 further including a first photodetector for receiving radiation transmitted by said first filter and a second photodetector for receiving radiation transmitted by said second filter.
Claim 7
Dependent Claim
29 words
The hygrometer of claim 1 in which said means for comparing includes means for normalizing the intensity of the radiation transmitted in each of said first and second regions.
Claim 8
Dependent Claim
41 words
The hygrometer of claim 6 in which said means for comparing and said means for normalizing includes means for dividing the intensity of the radiation transmitted in said first region by the intensity of the radiation transmitted in said second region.
Claim 9
Dependent Claim
41 words
The hygrometer of claim 6 in which said means for comparing and said means for normalizing includes means for subtracting the intensity of the radiation transmitted in said second region from the intensity of the radiation transmitted in the first region.
Claim 10
Dependent Claim
43 words
The hygrometer of claim 1 in which said means for determining includes means for retrieving a stored predetermined value for the amount of water in the sample path corresponding to the compared intensities of the radiation transmitted in said first and second regions.
Claim 11
Dependent Claim
22 words
The hygrometer of claim 1 in which said means for determining includes means for calculating the amount of water in the sample.
Claim 12
Dependent Claim
42 words
The hygrometer of claim 1 further including means for sensing the temperature of said sample, said means for determining being further responsive to said means for sensing for converting the determined amount of water in the sample into water of relative humidity.
Claim 13
Dependent Claim
22 words
The hygrometer of claim 1 in which said means for determining includes means for resolving the absolute humidity in the sample path.
Claim 14
Dependent Claim
22 words
The hygrometer of claim 1 in which said means for determining includes means for resolving the relative humidity in the sample path.
Claim 15
Dependent Claim
21 words
The hygrometer of claim 1 further including feedback means for controlling the intensity of the radiation transmitted in said second region.
Claim 16
Dependent Claim
24 words
The hygrometer of claim 1 further including means responsive to said means for determining for displaying the water content determined in the sample path.
Claim 17
Dependent Claim
24 words
The hygrometer of claim 1 further including means responsive to said means for determining for recording the water content determined in the sample path.
Claim 18
Dependent Claim
21 words
The hygrometer of claim 1 further including conduit means for conducting said radiation from said source to said means for detecting.
Claim 19
Dependent Claim
21 words
The hygrometer of claim 17 in which said conduit means includes first and second conduit portions separated by said sample path.
Claim 20
Dependent Claim
46 words
The hygrometer of claim 18 including first optical means for receiving radiation from said first conduit portion and transmitting said radiation through the sample path and second optical means for receiving the radiation transmitted through the sample path and transmitting it to said second conduit portion.
Claim 21
Dependent Claim
13 words
The hygrometer of claim 17 in which said conduit means includes fiber optics.
Claim 22
Dependent Claim
23 words
The hygrometer of claim 18 further including a housing for holding said conduit means with their ends fixed relative to said sample path.
Claim 23
Dependent Claim
12 words
The hygrometer of claim 19 in which said optical means include prisms.
Claim 24
Dependent Claim
25 words
The hygrometer of claim 19 further including means for providing a fluid flow over said optical means to keep said optical means clean of contaminants.
Claim 25
Dependent Claim
13 words
The hygrometer of claim 19 in which said optical means include reflective elements.
Claim 26
Dependent Claim
37 words
The hygrometer of claim 1 in which said means for detecting includes a first photosensor which senses only radiation in said first wavelength region and a second photosensor which senses only radiation in said second wavelength region.
Claim 27
Dependent Claim
116 words
An ultraviolet hygrometer comprising: a source of pulsed ultraviolet radiation for providing radiation in a first wavelength region where water absorbs significantly and in a second proximate wavelength region where water absorbs weakly; a housing including conduit means for conducting said radiation therethrough, said conduit means having first and second portions separated by a space for containing a sample path; means for detecting ultraviolet radiation in said first and second regions transmitted through the sample path; means, responsive to said means for detecting, for comparing the intensity of the radiation transmitted in each of first and second regions; and means, responsive to said means for comparing, for determining the amount of water in the sample path.
Claim 28
Dependent Claim
116 words
An ultraviolet hygrometer comprising: a source of pulsed ultraviolet radiation for providing radiation in a first wavelength region where water absorbs significantly and in a second proximate wavelength region where water absorbs weakly; a housing including conduit means for conducting said radiation therethrough, said conduit means having first and second portions separated by a space for containing a sample path; means for detecting ultraviolet radiation in said first and second regions transmitted through the sample path; means, responsive to said means for detecting, for comparing the intensity of the radiation transmitted in each of first and second regions; and means, responsive to said means for comparing, for determining the amount of water in the sample path.
Claim 29
Dependent Claim
49 words
The hygrometer of claim 26 further including first optical means for receiving said radiation from said first conduit portion and transmitting said radiation through the sample path and second optical means for receiving the radiation transmitted through the sample path and transmitting said radiation to said second conduit portion.
Claim 30
Dependent Claim
13 words
The hygrometer of claim 27 in which said conduit means includes fiber optics.
Claim 31
Dependent Claim
12 words
The hygrometer of claim 27 in which said optical means include prisms.
Claim 32
Dependent Claim
13 words
The hygrometer of claim 27 in which said optical means include reflective elements.
Claim 33
Dependent Claim
25 words
The hygrometer of claim 26 further including means for providing a fluid flow over said optical means to keep said optical means clear of contaminants.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-08 | 1990-06-09 | 1990-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-08 | 1994-06-09 | 1994-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-08 | 1998-06-09 | 1998-12-09 | $7700.00 | Window Closed / Lapsed |