Patent US3497577A successfully refreshed from Google Patents.
US3497577A
Expired / Lapsed
US
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Method of production of plastic lenses with aspherical surfaces
Assignee: Czech Academy of Sciences
•
Filing: 1967-02-14
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Granted: 1970-02-24
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Expires: 1987-02-14
Abstract
No abstract record available.
Inventors
- 👤 Otto Wichterle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:47
CPC Classifications
B; B29; B29D; B29D11/00; B29D11/00009; B29D11/00019; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2252504A
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US2305945A
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US2319014A
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US3038210A
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US3000057A
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US3171869A
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US3079736A
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US3064401A
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US3079737A
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US3361858A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-02-23 | 1973-08-25 | 1974-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-02-23 | 1977-08-25 | 1978-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-02-23 | 1981-08-25 | 1982-02-24 | $7700.00 | Window Closed / Lapsed |