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US3620147A
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US
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Photometric device for photometering within a polomirror body for use with a single-lens reflex camera
Assignee: Ricoh Co Ltd
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Filing: 1968-09-19
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Granted: 1971-11-16
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Expires: 1988-09-19
Abstract
Abstract AN EXPOSURE METER DEVICE FOR USE WITH A SINGLE-LENS REFLEX CAMERA WHEREIN THE VIEWFINDER SYSTEM INCLUDES A POLOMIRROR BODY (HOLLOW POLYHEDRON FORMED OF PLASTIC MATERIAL OR THE LIKE AND PROVIDED WITH INTERNAL LIGHT REFLECTING SURFACES), AND A LIGHT RECEIVING MEMBER IS LOCATED WITHIN OR MOVABLE INTO THE POLOMIRROR AND POSITIONED IN THE OPTICAL PATH OF THE VIEWFINDER.
Inventors
- 👤 Hisanori Ataka
- 👤 Yohei Ikezu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:35
CPC Classifications
G; G03; G03B; G03B19/00; G03B19/02; G03B19/12; G03B7/00; G03B7/08; G03B7/099; G03B7/0993; G03B7/0997; G03B7/09971; G03B7/09976
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) | 1974-11-15 | 1975-05-17 | 1975-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-15 | 1979-05-17 | 1979-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-15 | 1983-05-17 | 1983-11-16 | $7700.00 | Window Closed / Lapsed |