Patent US2997590A successfully refreshed from Google Patents.
US2997590A
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Infrared radiation entrance window
Assignee: International Business Machines Corp
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Filing: 1959-06-26
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Granted: 1961-08-22
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Expires: 1979-06-26
Abstract
No abstract record available.
Inventors
- 👤 Vincent J Lyons
- 👤 Gene A Silvey
- 👤 William J Turner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:39
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/20; G02B5/207
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
69 words
APPARATUS FOR DETERMINING THE PRESENCE OF FOREIGN OBJECTS EMITTING INFRARED RADIATION AT ANY WAVELENGTH IN THE RANGE 1.3-30 MICRONS COMPRISING AN ENTRANCE WINDOW THROUGH WHICH SAID RADIATION MAY PASS CONSISTING ESSENTIALLY OF CRYSTALLINE CDAS2 OF TETRAGONAL SYMMETRY HAVING PRESENT THEREIN AN IMPURITY CONTENT OF LESS THAN 10**16 NET CARRIERS PER CC. ORIENTED WITH ITS C-AXIS IN THE PATH OF THE INFRARED RADIATION AND AN OPTICAL DETECTOR FOR SAID RADIATION.
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) | 1964-08-21 | 1965-02-20 | 1965-08-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-08-21 | 1969-02-20 | 1969-08-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-08-21 | 1973-02-20 | 1973-08-22 | $7700.00 | Window Closed / Lapsed |