US2795993A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vision testing set
Assignee: American Optical Corp
•
Filing: 1953-06-30
•
Granted: 1957-06-18
•
Expires: 1973-06-30
Abstract
No abstract record available.
Inventors
- 👤 Hollis M Leverett
- 👤 Lawrence R Travis
- 👤 Milton R Thorburn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:52
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US718293A
Cited
US1719733A
Cited
US1749612A
Cited
US1920428A
Cited
US2240156A
Cited
US2466958A
Cited
US2478662A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-06-17 | 1960-12-17 | 1961-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-06-17 | 1964-12-17 | 1965-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-06-17 | 1968-12-17 | 1969-06-18 | $7700.00 | Window Closed / Lapsed |