US2491312A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for ophthalmic measurements
Assignee: Individual
•
Filing: 1948-07-20
•
Granted: 1949-12-13
•
Expires: 1968-07-20
Abstract
No abstract record available.
Inventors
- 👤 Ferdinand G Henry
- 👤 George W Stark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:52
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/11; G; G02; G02C; G02C13/00; G02C13/003; G02C13/005
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-12 | 1953-06-13 | 1953-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-12 | 1957-06-13 | 1957-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-12 | 1961-06-13 | 1961-12-13 | $7700.00 | Window Closed / Lapsed |