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Patent US2901679A successfully refreshed from Google Patents.
US2901679A
Expired / Lapsed
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Ferroelectric devices
Assignee: AT&T Inc
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Filing: 1955-02-18
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Granted: 1959-08-25
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Expires: 1975-02-18
Abstract
No abstract record available.
Inventors
- 👤 Bernd T Matthias
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:10
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/45; G; G11; G11C; G11C11/00; G11C11/21; G11C11/22; H01; H01G; H01G7/00; H01G7/02; H01G7/021; H10; H10N; H10N30/00; H10N30/80; H10N30/85; H10N30/857
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
39 words
AN ELECTRICAL MEMORY DEVICE WHICH COMPRISES IN COMBINATION A FERROELECTRIC ELEMENT OF CRYSTYALLINE MATERIAL COMPRISING GUANIDINUM ALUMINUM SULPHATE HEXAHYDRATE IN THE TRIGONAL FORM AND A PAIR OF ELECTRODES COUPLED IN ELECTRICAL CONTACTING RELATION WITH THE SURFACES OF SAID ELEMENT.
Claim 2
Dependent Claim
39 words
AN ELECTRICAL MEMORY DEVICE WHICH COMPRISES IN COMBINATION A FERROELECTRIC ELEMENT OF CRYSTYALLINE MATERIAL COMPRISING GUANIDINUM ALUMINUM SULPHATE HEXAHYDRATE IN THE TRIGONAL FORM AND A PAIR OF ELECTRODES COUPLED IN ELECTRICAL CONTACTING RELATION WITH THE SURFACES OF SAID ELEMENT.
References Cited (Backward Citations)
US2717372A
Cited
US2699666A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-08-24 | 1963-02-23 | 1963-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-24 | 1967-02-23 | 1967-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-24 | 1971-02-23 | 1971-08-25 | $7700.00 | Window Closed / Lapsed |