Patent US4837594A successfully refreshed from Google Patents.
US4837594A
Expired / Lapsed
US
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Automatic focusing device and automatic exposure control device
Assignee: Minolta Co Ltd
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Filing: 1988-02-25
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Granted: 1989-06-06
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Expires: 2008-02-25
Abstract
Abstract An automatic focusing device which compises a defocus amount detecting unit for detecting a defocus amount attributable to a first optical system of an interchangeable lens assembly and a second optical system of an AF convertor, a converting circuit for converting the defocus amount into a data corresponding to a focusing amount of the second optical system which varies in non-linear relationship to the defocus amount, and an optical drive unit for moving the second optical system on the basis of a data representative of the focusing amount supplied from the converting circuit.
Inventors
- 👤 Akiyoshi Nakamura
- 👤 Makoto Ando
- 👤 Shuji Ogino
- 👤 Nobuyuki Taniguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:15
CPC Classifications
G; G03; G03B; G03B7/00; G03B7/08; G03B7/091; G02; G02B; G02B7/00; G02B7/28; G02B7/36
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
121 words
An automatic focusing device which comprises: a defocus amount detecting means for detecting a defocus amount attributable to a first optical system of an interchangeable lens assembly and a second optical system of an AF convertor; a focal length data outputting means for outputting focal length data representative of the focal length of the second optical system; a converting means for converting said defocus amount, taken into consideration with the focal length data, into data corresponding to a focusing amount of the second optical system which varies in non-linear relationship to said defocus amount; and an optical drive means for moving the second optical system on the basis of the data representative of the focusing amount supplied from the converting means.
Claim 2
Dependent Claim
121 words
An automatic focusing device which comprises: a defocus amount detecting means for detecting a defocus amount attributable to a first optical system of an interchangeable lens assembly and a second optical system of an AF convertor; a focal length data outputting means for outputting focal length data representative of the focal length of the second optical system; a converting means for converting said defocus amount, taken into consideration with the focal length data, into data corresponding to a focusing amount of the second optical system which varies in non-linear relationship to said defocus amount; and an optical drive means for moving the second optical system on the basis of the data representative of the focusing amount supplied from the converting means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-05 | 1992-12-05 | 1993-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-05 | 1996-12-05 | 1997-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-05 | 2000-12-05 | 2001-06-06 | $7700.00 | Window Closed / Lapsed |