US2853920A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Profile projectors
Assignee: Ernst Leitz Wetzlar GmbH
•
Filing: 1955-05-10
•
Granted: 1958-09-30
•
Expires: 1975-05-10
Abstract
No abstract record available.
Inventors
- 👤 Malfeld Otto
- 👤 Becker Helmut
- 👤 Mandler Walter
- 👤 Wetzlar Kreis
- 👤 Koch Artur
- 👤 Martin Ernst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:29
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/0004; G02B21/0016
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1424941A
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GB332017A
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FR779608A
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US2146506A
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US2391999A
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US2406451A
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US2552280A
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US2681592A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-09-29 | 1962-03-31 | 1962-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-29 | 1966-03-31 | 1966-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-29 | 1970-03-31 | 1970-09-30 | $7700.00 | Window Closed / Lapsed |