Patent US1644798A successfully refreshed from Google Patents.
US1644798A
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Ophthalmic lens
Assignee: American Optical Corp
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Filing: 1925-08-26
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Granted: 1927-10-11
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Expires: 1945-08-26
Abstract
No abstract record available.
Inventors
- 👤 Edgar D Tillyer
- 👤 Harold R Moulton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:51
CPC Classifications
C; C03; C03C; C03C17/00; C03C17/22; C03C17/23; C03C17/25; C03C17/253; C03C2217/00; C03C2217/20; C03C2217/21; C03C2217/211; C03C2218/00; C03C2218/10; C03C2218/11; Y; Y10; Y10S; Y10S359/00; Y10S359/90
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) | 1930-10-10 | 1931-04-11 | 1931-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-10-10 | 1935-04-11 | 1935-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-10-10 | 1939-04-11 | 1939-10-11 | $7700.00 | Window Closed / Lapsed |