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Patent US3630945A successfully refreshed from Google Patents.
US3630945A
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Divalent europium activated alkaline earth aluminum fluoride luminescent materials and process
Assignee: General Electric Co
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Filing: 1970-04-06
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Granted: 1971-12-28
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Expires: 1990-04-06
Abstract
Abstract SRALF5, BAALF5, AND BA3AL2F12, ALL ACTIVATED WITH DIVALENT EQUROPIUM SUBSTITUTING FOR THE ALKALINE EARTH METAL, ARE SHOWN TO BE EFFICIENT PRODUCERS OF SHARP LINE ULTRAVIOLETE EMISSION RESULTING FROM 4F TO 4F ENERGY LEVEL TRANSISTIONS IN THE DIVALENT EUROPIUM, AS CONTRASTED TO PREVIOUS LUMINESCENT MATERIALS UTLIZING DIVALENT EUROPIUM AS AN ACTIVATOR IN WHICH THE EMISSION IS BAND DUE TO 5D TO 4F TRANSITIONS. SOLID STATE AND PRECIPITATION METHODS FOR PRODUCING THESE PHOSPHORS ARE DISCLOSED, THESE MATERIALS ARE USEFUL A PHOSPHORS IN CATHODE RAY TUBES, LAMPS, AND OTHER APPLICATIONS.
Inventors
- 👤 Mary V Hoffman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:09
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7728; C09K11/7732; C09K11/7733
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |