Patent US2507255A successfully refreshed from Google Patents.
Patent US3225173A successfully refreshed from Google Patents.
US3225173A
Expired / Lapsed
US
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Anti-frost apparatus for optical element
Assignee: Individual
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Filing: 1963-07-12
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Granted: 1965-12-21
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Expires: 1983-07-12
Abstract
No abstract record available.
Inventors
- 👤 Richard T Cook
- 👤 Warren D Hallermeier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:31
CPC Classifications
G; G05; G05D; G05D23/00; G05D23/19; G05D23/20; G05D23/24; G02; G02B; G02B27/00; G02B27/0006; G05D23/1927; G05D23/193; G05D23/1931; H; H05; H05B; H05B3/00; H05B3/84
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
111 words
THE COMBINATION WITH AN OPTICAL INSTRUMENT HAVING ENCLOSURE MEANS AND AN OUTER OPTICAL ELEMENT PROVIDING A LIGHT-TRANSMITTING VIEWING WINDOW IN SAID ENCLOSURE MEANS, OF ELECTRICAL CONTROL APPARATUS FOR KEEPING AN EXPOSED OUTER SURFACE OF SAID OPTICAL ELEMENT FREE FROM DEPOSITION OF MOISTURE FROM THE SURROUDING ATMOSPHERE UNDER VARYING AMBIENT TEMPERATURE CONDITIONS, SAID APPARATUS COMPRISING FIRST TEMPERATURE-SENSING ELECTRICAL RESISTANCE MEANS CONTIGUOUS TO THE EXPOSED OUTER SURFACE OF SAID OPTICAL ELEMENT, SECOND TEMPERATURE-SENSING ELECTRICAL RESISTANCE MEANS IN THE OUTER AMBIENT ATMOSPHERE SURROUNDING SAID SURFACE IN SPACED RALATION TO SAID FIRST RESISTANCE MEANS, A SOURCE OF ELECTRICAL OPERATING CURRENT, ELECTRICALLY-CONDUCTIVE TRANSLUCENT HEATING MEANS FOR THE OUTER SURFACE OF SAID OPTICAL ELEMENT, AND ELECTRICAL BRIDGE
Claim 2
Dependent Claim
111 words
THE COMBINATION WITH AN OPTICAL INSTRUMENT HAVING ENCLOSURE MEANS AND AN OUTER OPTICAL ELEMENT PROVIDING A LIGHT-TRANSMITTING VIEWING WINDOW IN SAID ENCLOSURE MEANS, OF ELECTRICAL CONTROL APPARATUS FOR KEEPING AN EXPOSED OUTER SURFACE OF SAID OPTICAL ELEMENT FREE FROM DEPOSITION OF MOISTURE FROM THE SURROUDING ATMOSPHERE UNDER VARYING AMBIENT TEMPERATURE CONDITIONS, SAID APPARATUS COMPRISING FIRST TEMPERATURE-SENSING ELECTRICAL RESISTANCE MEANS CONTIGUOUS TO THE EXPOSED OUTER SURFACE OF SAID OPTICAL ELEMENT, SECOND TEMPERATURE-SENSING ELECTRICAL RESISTANCE MEANS IN THE OUTER AMBIENT ATMOSPHERE SURROUNDING SAID SURFACE IN SPACED RALATION TO SAID FIRST RESISTANCE MEANS, A SOURCE OF ELECTRICAL OPERATING CURRENT, ELECTRICALLY-CONDUCTIVE TRANSLUCENT HEATING MEANS FOR THE OUTER SURFACE OF SAID OPTICAL ELEMENT, AND ELECTRICAL BRIDGE
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) | 1968-12-20 | 1969-06-21 | 1969-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-12-20 | 1973-06-21 | 1973-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-12-20 | 1977-06-21 | 1977-12-21 | $7700.00 | Window Closed / Lapsed |