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US2901679A Expired / Lapsed US ⏱️ 0.0 years remaining

Ferroelectric devices

Assignee: AT&T Inc
•
Filing: 1955-02-18
•
Granted: 1959-08-25
•
Expires: 1975-02-18
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Abstract

No abstract record available.

Inventors

  • 👤 Bernd T Matthias

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 15:13
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

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