US3615137A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Focussing device for optical system
Assignee: Canon Inc
•
Filing: 1967-10-09
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Granted: 1971-10-26
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Expires: 1987-10-09
Abstract
Abstract THE PRESENT INVENTION PROVIDES A FOCUSSING DEVICE FOR FOCUSSING THE IMAGE OF AN OBJECT IN A FOCAL PLATE COMPRISING AN OBJECTIVE LENS MOVABLE RELATIVE TO THE FOCAL PLANE A CURRENT MEASURING DEVICE, AND AN ELECTRICAL CIRCUIT INCLUDING A SOURCE OF VOLTAGE INTERCONNECTING THE CELL AND THE DEVICE, THE FOCAL PLANE OF THE PHOTOCONDUCTIVE CELLS BEING OF A PHOTOCONDUCTIVE MATERIAL HAVING A PROPERTY SPECIFIC TO THE PHOTOCONDUCTIVE MATERIAL USED, THE CURRENT MEASURING DEVICE MEASUREMENT THE EXTREME VALUE OF THE CURRENT FLOWING THROUGH THE CIRCUIT FOR THE EXTREME VALUE OF THE RESISTIVITY OF THE CELL WHEN THE TOTAL LIGHT RAYS FOCUS TO A SHARP IMAGE ON THE CELL.
Inventors
- 👤 Isao Yamaguchi
- 👤 Tatsushi Kitanosono
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:58
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/28; G02B7/34
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) | 1974-10-25 | 1975-04-26 | 1975-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-25 | 1979-04-26 | 1979-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-25 | 1983-04-26 | 1983-10-26 | $7700.00 | Window Closed / Lapsed |