Patent DE2529079C2 successfully refreshed from Google Patents.
US4538892A
Expired / Lapsed
US
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Automatic focus control system
Assignee: Canon Inc
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Filing: 1983-07-20
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Granted: 1985-09-03
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Expires: 2003-07-20
Abstract
Abstract This specification discloses an energizing control of a drive element for driving a motor or the like which drives a focusing lens. The energization is controlled on the basis of the detection of whether or not the position of the focusing lens is within the quasi-in-focus state, and when the continuation of the quasi-in-focus state for a predetermined time period or more is detected, energization of the driving element is stopped.
Inventors
- 👤 Shinji Sakai
- 👤 Yoshihito Harada
- 👤 Akira Ishizaki
- 👤 Takashi Kawabata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:39
CPC Classifications
G; G03; G03B; G03B3/00; G03B3/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
173 words
An automatic focus control system comprising: (a) distance detecting means for outputting a distance detective signal corresponding to a distance of an object to be photographed; (b) drive means for driving a focusing lens; (c) quasi-in-focus range detecting means for outputting, on the basis of the distance detection signal from said distance detecting means, a signal indicative of whether or not the focusing lens is in a quasi-in-focus range; (d) in-focus range detecting means for outputting, on the basis of the distance signal from said distance detecting means, a signal indicative of whether or not the focusing lens is in-focus; and (e) quasi-in-focus range continuation detecting means having memory means for receiving the output signal from said quasi-in-focus range detecting means indicating that said focusing lens is in the quasi-in-focus state and for outputting a control signal when said memory means receives a plurality of signals indicating that said focusing lens is in the quasi-in-focus range; wherein said drive means is controlled on the basis of the control signal from said memory means.
Claim 2
Dependent Claim
173 words
An automatic focus control system comprising: (a) distance detecting means for outputting a distance detective signal corresponding to a distance of an object to be photographed; (b) drive means for driving a focusing lens; (c) quasi-in-focus range detecting means for outputting, on the basis of the distance detection signal from said distance detecting means, a signal indicative of whether or not the focusing lens is in a quasi-in-focus range; (d) in-focus range detecting means for outputting, on the basis of the distance signal from said distance detecting means, a signal indicative of whether or not the focusing lens is in-focus; and (e) quasi-in-focus range continuation detecting means having memory means for receiving the output signal from said quasi-in-focus range detecting means indicating that said focusing lens is in the quasi-in-focus state and for outputting a control signal when said memory means receives a plurality of signals indicating that said focusing lens is in the quasi-in-focus range; wherein said drive means is controlled on the basis of the control signal from said memory means.
Claim 3
Dependent Claim
156 words
An automatic focus control system comprising: (a) distance detecting means for outputting a distance detection signal corresponding to a distance of an object to be photographed; (b) drive means for driving a focusing lens; (c) quasi-in-focus range detecting means for outputting, on the basis of the distance detection signal from said distance detecting means, a signal indicative of whether or not the focusing lens is in a quasi-in-focus range (d) in-focus range detecting means for outputting, on the basis of the distance signal from said distance detecting means, a signal indicative of whether or not the focusing lens is in-focus; and (e) quasi-in-focus range continuation detecting means having time-constant means for receiving the output signal from said quasi-in-focus range detecting means indicating that said focusing lens is in the quasi-in-focus range and for outputting a control signal after the predetermined time, said drive means being stopped in accordance with the control signal from said time-constant means.
Claim 4
Dependent Claim
156 words
An automatic focus control system comprising: (a) distance detecting means for outputting a distance detection signal corresponding to a distance of an object to be photographed; (b) drive means for driving a focusing lens; (c) quasi-in-focus range detecting means for outputting, on the basis of the distance detection signal from said distance detecting means, a signal indicative of whether or not the focusing lens is in a quasi-in-focus range (d) in-focus range detecting means for outputting, on the basis of the distance signal from said distance detecting means, a signal indicative of whether or not the focusing lens is in-focus; and (e) quasi-in-focus range continuation detecting means having time-constant means for receiving the output signal from said quasi-in-focus range detecting means indicating that said focusing lens is in the quasi-in-focus range and for outputting a control signal after the predetermined time, said drive means being stopped in accordance with the control signal from said time-constant means.
Claim 5
Dependent Claim
158 words
An automatic focus control system comprising: (a) distance detecting means for outputting a distance signal corresponding to a distance of an object to be photographed; (b) lens position signal generator means for outputting a signal corresponding to a position of a focusing lens; (c) drive means for driving a focusing lens; (d) means for receiving the output of said lens position signal generator means and the output signal from said distance detecting means to output a focus state signal; (e) first means, based on the focus state signal, for outputting a signal indicating that said focusing lens is in the quasi-in-focus range; (f) second means, based on the focus state signal, for outputting a signal indicating that said focusing lens is in-focus; and (g) time control means for receiving the signal from said first means and for stopping the energization of said drive means after a predetermined time from the receipt of the signal from said first means.
Claim 6
Dependent Claim
158 words
An automatic focus control system comprising: (a) distance detecting means for outputting a distance signal corresponding to a distance of an object to be photographed; (b) lens position signal generator means for outputting a signal corresponding to a position of a focusing lens; (c) drive means for driving a focusing lens; (d) means for receiving the output of said lens position signal generator means and the output signal from said distance detecting means to output a focus state signal; (e) first means, based on the focus state signal, for outputting a signal indicating that said focusing lens is in the quasi-in-focus range; (f) second means, based on the focus state signal, for outputting a signal indicating that said focusing lens is in-focus; and (g) time control means for receiving the signal from said first means and for stopping the energization of said drive means after a predetermined time from the receipt of the signal from said first means.
References Cited (Backward Citations)
US4091275A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |