US3657644A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermodielectric radiometer utilizing polymer film
Assignee: National Aeronautics and Space Administration
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Filing: 1968-11-12
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Granted: 1972-04-18
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Expires: 1988-11-12
Abstract
Abstract A thermodielectric radiometer employing a polymer film or a capacitor dielectric. The film is charged to a suitable voltage gradient and, when it is heated by absorbed radiation, it produces a proportional open-circuit voltage increment which can be measured to provide an indication of the total energy or power of a short-duration pulse of radiant flux. The invention described herein was made by employees of the United States Government and may be manufactured and used by or for the Government for governmental purposes without the payment of any royalties thereon or therefor.
Inventors
- 👤 Benjamin H Beam
- 👤 Larry D Russell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 00:52
CPC Classifications
H; H10; H10N; H10N15/00; H10N15/10; G; G01; G01J; G01J5/00; G01J5/10; G01J5/34; G01K; G01K7/00; G01K7/34; G01K7/343
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
39 words
Apparatus in accordance with claim 1 wherein the opposite surfaces of said dielectric film each have at least one electrode placed thereon; and said charging means comprises a diode, a resistance, and a d-c voltage source connected in series.
Claim 2
Dependent Claim
32 words
Apparatus in accordance with claim 2 including a housing for said capacitor, said housing having an opening therein, said capacitor, being positioned adjacent said opening to receive radiant energy entering said opening.
Claim 3
Dependent Claim
26 words
Apparatus in accordance with claim 2 including a substance of high absorptivity deposited on one of said electrodes to increase the radiation absorption of said capacitor.
Claim 4
Dependent Claim
230 words
Apparatus for detecting radiant energy in the presence of electromagnetic noise comprising: a capacitor having a polymer film dielectric; means coupled to said capacitor for continuously charging said capacitor to a predetermined open-circuit d-c voltage; means for exposing said polymer film dielectric to the radiant energy to be detected to produce thermal depolarization in said polymer film dielectric, said thermal depolarization generating an open-circuit voltage increment proportional to said predetermined voltage and said radiant energy; detection means connected to said capacitor to detect said open-circuit voltage increment to provide a measure of said radiant energy; said capacitor comprising first and second electrodes disposed on one surface of said dielectric film and a third electrode coextensive with said first and second electrodes disposed on the opposite surface of said dielectric film, said first electrode, said third electrode, and said polymer film dielectric therebetween forming a capacitor section, said second electrode, said third electrode, and said polymer film dielectric therebetween forming another capacitor section; said exposing means exposing one of said capacitor sections to both said radiant energy and said electromagnetic noise and exposing said other capacitor section to only said electromagnetic noise; and said detection means including differential amplifying means connected to said capacitors for differentially amplifying the increases in open-circuit voltage thereacross as a result of thermal depolarization of said film dielectric, to thereby reduce the effect of said noise.
Claim 5
Dependent Claim
61 words
Apparatus in accordance with claim 5 including a housing, said housing having a first window therein which is transparent to both said radiant energy and said noise, and having a second window therein which is transparent only to said noise, said one capacitor section being positioned adjacent said first window and said other capacitor section being positioned adjacent said second window.
Claim 6
Dependent Claim
24 words
Apparatus in accordance with claim 6 including preamplifier means disposed in said housing and connected between said capacitor sections and said differential amplifying means.
Claim 7
Dependent Claim
25 words
Apparatus in accordance with claim 5 including a substance of high absorptivity on said third electrode to increase the radiation absorPtion of said capacitor sections.
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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) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |