Patent US3715165A successfully refreshed from Google Patents.
US3715165A
Expired / Lapsed
US
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Investigating the topography of reflecting surfaces
Assignee: Vickers Ltd
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Filing: 1971-06-07
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Granted: 1973-02-06
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Expires: 1991-06-07
Abstract
Abstract A SPECIMEN SURFACE IS INVESTIGATED WITH AN OPTICAL ARRANGEMENT THAT BRINGS A PENCIL OF LIGHT TO A POINT FOCUS WHICH OSCILLATES LONGTUDINALLY ABOUT THE SURFACE. IN DEPENDENCE UPON LIGHT REFLECTED FROM THE SURFACE, PHOTOELECTRONIC MEANS PROVIDE AN ELECTRIC SIGNAL CONTROLLING DISPLACEMENT OF A REFLECTING SURFACE OF THE ARRANGEMENT TO BRING THE MEANS POSITION ABOUT WHICH THE FOCUS OSCILLATES TOWARDS COINCIDENCE WITH THE SURFACE.
Inventors
- 👤 F Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:33
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/87; G01B; G01B11/00; G01B11/30; G02; G02B; G02B7/00; G02B7/28
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-06 | 1976-08-07 | 1977-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-06 | 1980-08-07 | 1981-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-06 | 1984-08-07 | 1985-02-06 | $7700.00 | Window Closed / Lapsed |