Patent US2256133A successfully refreshed from Google Patents.
US2256133A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refractive equalizer
Assignee: E R FENIMORE JOHNSON
•
Filing: 1940-10-26
•
Granted: 1941-09-16
•
Expires: 1960-10-26
Abstract
No abstract record available.
Inventors
- 👤 George W Barnes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:47
CPC Classifications
G; G03; G03B; G03B17/00; G03B17/02; G03B17/08
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1944-09-15 | 1945-03-17 | 1945-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-09-15 | 1949-03-17 | 1949-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-09-15 | 1953-03-17 | 1953-09-16 | $7700.00 | Window Closed / Lapsed |