Patent US3517992A successfully refreshed from Google Patents.
US3517992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic focusing slide projector
Assignee: Ernst Leitz Wetzlar GmbH
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Filing: 1969-04-21
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Granted: 1970-06-30
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Expires: 1989-04-21
Abstract
No abstract record available.
Inventors
- 👤 Werner Holle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:47
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/14; G03B21/53
Claims Analysis
Total Claims: 0
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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) | 1973-06-29 | 1973-12-29 | 1974-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-29 | 1977-12-29 | 1978-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-29 | 1981-12-29 | 1982-06-30 | $7700.00 | Window Closed / Lapsed |