US2481582A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Eye testing device having self-contained means for checking both far and near vision deficiencies
Assignee: American Optical Corp
•
Filing: 1945-10-19
•
Granted: 1949-09-13
•
Expires: 1965-10-19
Abstract
No abstract record available.
Inventors
- 👤 Charles A Ellis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:45
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/02; A61B3/028; A61B3/032
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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FR386733A
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US1417283A
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US1454774A
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US1526781A
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GB199219A
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US1953268A
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US1949067A
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US2206303A
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US2238207A
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US2294787A
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US2362588A
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US2364793A
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US2394711A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-09-12 | 1953-03-14 | 1953-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-09-12 | 1957-03-14 | 1957-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-09-12 | 1961-03-14 | 1961-09-13 | $7700.00 | Window Closed / Lapsed |