Patent US5946504A successfully refreshed from Google Patents.
US5946504A
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Automatic focus adjusting device in camera system
Assignee: Canon Inc
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Filing: 1994-10-28
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Granted: 1999-08-31
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Expires: 2014-10-28
Abstract
Abstract An automatic focus adjusting device in a camera system includes a focus detecting circuit for a focusing state of an object image formed on an image plane by a photographic lens, a control circuit for producing a control signal on the basis of an output of the focus detecting circuit and for outputting the control signal to the photographic lens to control the same, and a characteristic detecting circuit for detecting a predetermined optical characteristic of the photographic lens. The control circuit is arranged to transmit the control signal to the photographic lens by defining as a parameter a change of the optical characteristic detected by the characteristic detecting circuit.
Inventors
- 👤 Masahide Hirasawa
- 👤 Naoya Kaneda
- 👤 Hiroyuki Wada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 20:46
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/60; H04N23/66; H04N23/663; H04N23/67; H04N23/673
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
175 words
A video camera device, comprising: (A) a lens unit including a variator lens and a focusing lens; (B) image sensing means for converting an optical image formed by the lens unit into an electrical signal to output an image signal; (C) focus detection means for detecting a focus condition from the image signal output by the image sensing means; (D) memory means for memorizing a movement locus information of the focusing lens for maintaining an in-focus condition with correction of variation in position of the in-focus caused by movement of the variator lens; (E) first correction means for driving the focusing lens according to the movement locus information read out from the memory means on the basis of the positions of the focusing lens and the variator lens during a zooming operation; and (F) second correction means for shifting the position of the focusing lens back or forth relative to the movement locus information selected by said first correction means according to variation in the output of the focus detection means during the zooming operation.
Claim 2
Dependent Claim
175 words
A video camera device, comprising: (A) a lens unit including a variator lens and a focusing lens; (B) image sensing means for converting an optical image formed by the lens unit into an electrical signal to output an image signal; (C) focus detection means for detecting a focus condition from the image signal output by the image sensing means; (D) memory means for memorizing a movement locus information of the focusing lens for maintaining an in-focus condition with correction of variation in position of the in-focus caused by movement of the variator lens; (E) first correction means for driving the focusing lens according to the movement locus information read out from the memory means on the basis of the positions of the focusing lens and the variator lens during a zooming operation; and (F) second correction means for shifting the position of the focusing lens back or forth relative to the movement locus information selected by said first correction means according to variation in the output of the focus detection means during the zooming operation.
Claim 3
Dependent Claim
30 words
A video camera device according to claim 1, wherein said second correcting means operates only when the driving direction of said variator lens is from the wide to the tele.
Claim 4
Dependent Claim
40 words
A video camera device according to claim 1, wherein said second correcting means moves the focusing lens back and forth relative to the movement locus at such a speed that a changing speed of a circle of confusion is same.
Claim 5
Dependent Claim
32 words
A video camera device according to claim 1, wherein said second correcting means moves the focusing lens in such a manner that defocus is caused always first at a far focus side.
Claim 6
Dependent Claim
25 words
A video camera device according to claim 1, wherein said memory means is stored with a plurality of movement loci according to an object distance.
Claim 7
Dependent Claim
20 words
A video camera device according to claim 1, wherein said second correcting means operates at a frequency of 1/60 second.
Claim 8
Dependent Claim
27 words
A video camera device according to claim 1, further comprising means for prohibiting a zoom operation by said variator lens during non-operation of said focus detection means.
Claim 9
Dependent Claim
130 words
A video camera device, comprising: (A) a lens unit including a variator lens and a focusing lens independently movable from each other; (B) image sensing means for converting an optical image formed by the lens unit into an electrical signal to output an image signal; (C) memory means for memorizing a movement locus of the focusing lens for maintaining the in-focus state with correction of variation in position of the in-focus caused by the movement of the variator lens; and (D) control means for driving the focusing lens according to the movement locus read out from the memory means on the basis of the positions of the focusing lens and the variator lens, and for varying the control of the focusing lens depending on movement directions of the variator lens.
Claim 10
Dependent Claim
130 words
A video camera device, comprising: (A) a lens unit including a variator lens and a focusing lens independently movable from each other; (B) image sensing means for converting an optical image formed by the lens unit into an electrical signal to output an image signal; (C) memory means for memorizing a movement locus of the focusing lens for maintaining the in-focus state with correction of variation in position of the in-focus caused by the movement of the variator lens; and (D) control means for driving the focusing lens according to the movement locus read out from the memory means on the basis of the positions of the focusing lens and the variator lens, and for varying the control of the focusing lens depending on movement directions of the variator lens.
Claim 11
Dependent Claim
45 words
A device according to claim 8, wherein the position of the focusing lens is shifted back and forth relative to the movement locus and is caused to follow the movement locus on the basis of the variation in the output of the in-focus detection means.
Claim 12
Dependent Claim
30 words
A video camera device according to claim 9, wherein said second correcting means operates only when the driving direction of said variator lens is from the wide to the tele.
Claim 13
Dependent Claim
40 words
A video camera device according to claim 10, wherein said second correcting means moves the focusing lens back and forth relative to the movement locus at such a speed that a changing speed of a circle of confusion is same.
Claim 14
Dependent Claim
32 words
A video camera device according to claim 11, wherein said second correcting means moves the focusing lens in such a manner that defocus is caused always first at a far focus side.
Claim 15
Dependent Claim
30 words
A video camera device according to claim 9, wherein said focus lens moves back and forth in a depth of field relative to the movement locus during a zooming operation.
Claim 16
Dependent Claim
134 words
A lens control device for a lens unit detachably attached to a camera body, comprising: (A) first lens means for varying an image magnification; (B) second lens means movable independently of said first lens means for performing a function of compensating of an in-focus position; (C) position detecting means for detecting positions of said first and second lens means; (D) memory means provided in said lens unit and memorized with a plurality of position information of the second lens means for maintaining an in-focus condition relative to a position of said first lens means; and (E) a micro computer for driving said second lens means according to the position information read out from said memory means according to the positions detected by said position detecting means and the position information of the in-focus condition.
Claim 17
Dependent Claim
134 words
A lens control device for a lens unit detachably attached to a camera body, comprising: (A) first lens means for varying an image magnification; (B) second lens means movable independently of said first lens means for performing a function of compensating of an in-focus position; (C) position detecting means for detecting positions of said first and second lens means; (D) memory means provided in said lens unit and memorized with a plurality of position information of the second lens means for maintaining an in-focus condition relative to a position of said first lens means; and (E) a micro computer for driving said second lens means according to the position information read out from said memory means according to the positions detected by said position detecting means and the position information of the in-focus condition.
Claim 18
Dependent Claim
28 words
A video camera device according to claim 14, wherein said micro-computer receives the position information of the in-focus condition from a camera micro-computer located on said camera body.
Claim 19
Dependent Claim
22 words
A video camera according to claim 15, wherein said control means controls the second lens means at a frequency of 1/60 second.
Claim 20
Dependent Claim
42 words
A video camera according to claim 14, wherein said micro-computer means computes a velocity of the second lens means for maintaining the in-focus condition according to the positions detected by said position detecting means and the position information of the in-focus condition.
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) | 2002-08-30 | 2003-03-01 | 2003-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-30 | 2007-03-01 | 2007-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-30 | 2011-03-01 | 2011-08-31 | $7700.00 | Window Closed / Lapsed |