Patent US3723739A successfully refreshed from Google Patents.
US3723739A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water-cooled cholesteric liquid crystal infrared imaging device
Assignee: United States Department of the Navy
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Filing: 1971-06-11
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Granted: 1973-03-27
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Expires: 1991-06-11
Abstract
Abstract An infrared imaging device for the detection and measurement of hazardous irradiances in a laser beam caused by atmospheric scintillation. The 10.6 micrometer field is displayed visibly through the use of cholesteric liquid crystals on a water-cooled mylar film.
Inventors
- 👤 R Horton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:04
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/132; G02B; G02B23/00; G02B23/12; H; H01; H01S; H01S3/00; H01S3/0014
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
26 words
A device as recited in claim 1 in which the cholesteric liquid crystal means comprises a layer of cholesteric liquid crystals applied to a supporting medium.
Claim 2
Dependent Claim
18 words
A device as recited in claim 2 in which the supporting medium comprises a sheet of mylar film.
Claim 3
Dependent Claim
23 words
A device as recited in claim 3 in which the mylar film''s thickness is in the range of from 0.0005 to 0.005 inch.
Claim 4
Dependent Claim
52 words
A device as recited in claim 2 in which the cooling means comprises a reservoir of circulating cooling-water of sufficient volume so as to enable extended operation of the imaging device over relatively high power average irradiances, said reservoir having means for raising, lowering and maintaining the cooling-water at a desired temperature.
Claim 5
Dependent Claim
50 words
A device as recited in claim 5 in which the supporting and holding means comprises a housing segmented into plural compartments, the first of said compartments being capable of holding said water reservoir and another of said compartments being a cavity positioned between said supporting medium and said first compartment.
Claim 6
Dependent Claim
56 words
A device as recited in claim 6 further comprising means for maintaining a water pressure head in said cavity and means for causing a turbulance region to exist in said cavity adjacent to said supporting medium to expedite heat transfer from said liquid crystal layer and said supporting medium to said cooling-water circulating through said cavity.
Claim 7
Dependent Claim
28 words
A device as recited in claim 7 in which said water pressure head maintaining means and turbulance region causing means comprise a rotatable impellor positioned in said cavity.
Claim 8
Dependent Claim
42 words
A device as recited in claim 2 in which said infrared radiation prevention means comprises a reflective coating of aluminum affixed to the opposite surface of said supporting medium from that surface to which said layer of cholesteric liquid crystals is applied.
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) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |