Patent US3405989A successfully refreshed from Google Patents.
US3405989A
Expired / Lapsed
US
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Inverted or metallographic type of microscopes
Assignee: Bausch and Lomb Inc
•
Filing: 1964-03-30
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Granted: 1968-10-15
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Expires: 1984-03-30
Abstract
No abstract record available.
Inventors
- 👤 John P Mentink
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:20
CPC Classifications
G; G02; G02B; G02B21/00; G02B21/0004; G02B21/0088; G02B21/02; G02B21/025
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2660923A
Cited
US2662443A
Cited
US3030861A
Cited
US3045545A
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US3202047A
Cited
US3237518A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-10-15 | 1972-04-15 | 1972-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-10-15 | 1976-04-15 | 1976-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-10-15 | 1980-04-15 | 1980-10-15 | $7700.00 | Window Closed / Lapsed |