Patent US3831401A successfully refreshed from Google Patents.
Patent US3521749A successfully refreshed from Google Patents.
US3521749A
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Techniques for detecting geometrical defects in regular shaped flat objects
Assignee: BRITISH SCIENT INSTR RESEARCH
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Filing: 1967-04-24
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Granted: 1970-07-28
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Expires: 1987-04-24
Abstract
No abstract record available.
Inventors
- 👤 Harmen Hein Dijstelbergen
- 👤 Anthony John Allnutt
- 👤 Richard Anthony Brook
- 👤 Robert Ernest Vickers Semos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:15
CPC Classifications
B; B07; B07C; B07C5/00; B07C5/04; B07C5/10; G; G01; G01B; G01B11/00; G01B11/24; G01B11/2433; G07; G07C; G07C3/00; G07C3/14
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2447024A
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US2346031A
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US2916633A
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US3060791A
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US3102960A
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US3312140A
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US3280692A
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US3226555A
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US3395794A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-07-27 | 1974-01-26 | 1974-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-27 | 1978-01-26 | 1978-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-27 | 1982-01-26 | 1982-07-28 | $7700.00 | Window Closed / Lapsed |