US2898477A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric field effect semiconductor device
Assignee: AT&T Inc
•
Filing: 1955-10-31
•
Granted: 1959-08-04
•
Expires: 1975-10-31
Abstract
No abstract record available.
Inventors
- 👤 Donald C Hoesterey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 17:22
CPC Classifications
H; H04; H04R; H04R23/00; H04R23/006; Y; Y10; Y10S; Y10S73/00; Y10S73/04
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2589983A
Cited
US2569347A
Cited
US2549550A
Cited
US2558563A
Cited
US2522521A
Cited
US2695357A
Cited
US2745010A
Cited
US2724171A
Cited
US2791759A
Cited
US2791758A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-08-03 | 1963-02-02 | 1963-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-03 | 1967-02-02 | 1967-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-03 | 1971-02-02 | 1971-08-04 | $7700.00 | Window Closed / Lapsed |