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Patent US3027806A successfully refreshed from Google Patents.
US3027806A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optical devices
Assignee: International Business Machines Corp
•
Filing: 1957-03-14
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Granted: 1962-04-03
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Expires: 1977-03-14
Abstract
No abstract record available.
Inventors
- 👤 Jr Albert C Koelsch
- 👤 Donald R Young
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:38
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F3/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2301743A
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US2254022A
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US2385086A
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US2600817A
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US2528510A
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US2616962A
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US2482242A
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US2670402A
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US2755996A
Cited
US2780958A
Cited
US2768557A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-04-02 | 1965-10-02 | 1966-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-04-02 | 1969-10-02 | 1970-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-04-02 | 1973-10-02 | 1974-04-03 | $7700.00 | Window Closed / Lapsed |