US1878973A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical instrument and method of treatment
Assignee: C W Dixey & Son Ltd
•
Filing: 1929-12-05
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Granted: 1932-09-20
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Expires: 1949-12-05
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:10
CPC Classifications
A; A61; A61H; A61H5/00; A61B; A61B3/00
Claims Analysis
Total Claims: 0
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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) | 1935-09-20 | 1936-03-21 | 1936-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-09-20 | 1940-03-21 | 1940-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-09-20 | 1944-03-21 | 1944-09-20 | $7700.00 | Window Closed / Lapsed |