US6088060A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic focusing device
Assignee: Canon Inc
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Filing: 1997-03-25
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Granted: 2000-07-11
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Expires: 2017-03-25
Abstract
Abstract An automatic focusing device for automatically controlling the focused state of an optical system on the basis of a video signal obtained within a focus detecting area which is set on an image sensing plane comprises: a tracing area setting circuit arranged to movably set, within said image sensing plane, an inner tracing area and an outer tracing area which surrounds the inner tracing area; a computing circuit arranged to compute information on a difference in a given frequency component of the video signal obtained from the inner and outer tracing areas in each of their different positions to which they are moved within the image sensing plane; determining means for determining the position or size of an object's image formed within the image sensing plane from the difference information computed by the computing circuit; and a circuit which is arranged to shift the focus detecting area to the position of the object's image determined by the determining circuit and to change the size of the focus detecting area according to the size of the object's image.
Inventors
- 👤 Hirofumi Suda
- 👤 Masamichi Toyama
- 👤 Akihiro Fujiwara
- 👤 Kunihiko Yamada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:57
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/28; G02B7/36; G02B7/365; H; H04; H04N; H04N23/00; H04N23/60; H04N23/61; H04N23/67; H04N23/673; H04N23/675
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
221 words
A video camera apparatus, comprising: (A) image sensing means for photoelectrically converting an object image formed on an image sensing plane to produce and output an image signal; (B) area setting means for setting a detecting area for detecting a photographing state of the object image on said image sensing plane; (C) detecting means for detecting a variation of a feature of the object image on the basis of the image signal corresponding to said detecting area in a first period of time; (D) control means for controlling said area setting means in a second period of time longer than said first period of time in accordance with an output of said detecting means and for causing the position and size of said detecting area on said image sensing plane to follow the variation of the feature of said object image, to independently change said detecting area in the first period; (E) focus detecting area setting means for setting a position of a focus detecting area in the second period of time at a center of said detecting area on said image sensing plane on the basis of the output of said detecting means; and (F) focus control means for adjusting a focus condition in the second period on the basis of the image signal corresponding to said focus detecting area.
Claim 2
Dependent Claim
221 words
A video camera apparatus, comprising: (A) image sensing means for photoelectrically converting an object image formed on an image sensing plane to produce and output an image signal; (B) area setting means for setting a detecting area for detecting a photographing state of the object image on said image sensing plane; (C) detecting means for detecting a variation of a feature of the object image on the basis of the image signal corresponding to said detecting area in a first period of time; (D) control means for controlling said area setting means in a second period of time longer than said first period of time in accordance with an output of said detecting means and for causing the position and size of said detecting area on said image sensing plane to follow the variation of the feature of said object image, to independently change said detecting area in the first period; (E) focus detecting area setting means for setting a position of a focus detecting area in the second period of time at a center of said detecting area on said image sensing plane on the basis of the output of said detecting means; and (F) focus control means for adjusting a focus condition in the second period on the basis of the image signal corresponding to said focus detecting area.
Claim 3
Dependent Claim
37 words
An apparatus according to claim 1, wherein said detecting means is arranged to detect a difference of levels of high frequency components in said image signal corresponding to an inside and an outside of said detecting area.
Claim 4
Dependent Claim
48 words
An apparatus according to claim 2, wherein said control means is arranged to shift the position to a position where the difference of levels of the high frequency components at the inside and the outside of the detecting area becomes maximum, in respect of said respective detecting area.
Claim 5
Dependent Claim
46 words
An apparatus according to claim 2, wherein said focus detecting area setting means is arranged to use, as the focus detecting area, the detecting area where the difference of levels of the high frequency components at the inside and outside of the detecting area becomes maximum.
Claim 6
Dependent Claim
189 words
A video processing apparatus, comprising: (A) area setting means for setting a plurality of work areas for measuring a position and/or size of an object image on an image plane; (B) detecting means for detecting a variation of the object image on the basis of a variation of predetermined signal components in an image signal in respect of an inner and outer part of the respective ones of said plurality of work areas in a first period of time; (C) control means for controlling said area setting means in accordance with an output of said detecting means and for measuring the position and/or size of the object image by causing the positions and/or sizes of said plurality of work areas on said image plane to follow the variation of the object image, to independently change the work areas, respectively in the first period of time; and (D) processing area setting means for setting in a second period of time longer than the first period of time a processing area at a position of the work area where the predetermined signal component becomes maximum among said plurality of work areas.
Claim 7
Dependent Claim
189 words
A video processing apparatus, comprising: (A) area setting means for setting a plurality of work areas for measuring a position and/or size of an object image on an image plane; (B) detecting means for detecting a variation of the object image on the basis of a variation of predetermined signal components in an image signal in respect of an inner and outer part of the respective ones of said plurality of work areas in a first period of time; (C) control means for controlling said area setting means in accordance with an output of said detecting means and for measuring the position and/or size of the object image by causing the positions and/or sizes of said plurality of work areas on said image plane to follow the variation of the object image, to independently change the work areas, respectively in the first period of time; and (D) processing area setting means for setting in a second period of time longer than the first period of time a processing area at a position of the work area where the predetermined signal component becomes maximum among said plurality of work areas.
Claim 8
Dependent Claim
30 words
An apparatus according to claim 5, further comprising correcting means for correcting the difference of levels of the predetermined signal component based on difference of sizes of said work areas.
Claim 9
Dependent Claim
36 words
An apparatus according to claim 5, wherein said control means is arranged to shift said plurality of work areas so that a difference of luminance between the inside and the outside of each area becomes maximum.
Claim 10
Dependent Claim
44 words
An apparatus according to claim 5, wherein said processing area setting means is arranged to adopt the work area where the difference of levels of the high frequency component between the inside and the outside of the area becomes maximum, as the processing area.
Claim 11
Dependent Claim
144 words
A video camera device, comprising: (A) image sensing means for photoelectrically converting an object image formed on an image sensing plane to produce and output an image signal; (B) area setting means for setting detecting areas on said image sensing plane; (C) detecting means for detecting a variation of the object image in a first period of time; (D) control means for controlling said area setting means in accordance with an output of said detecting means in a second period of time longer than the first period of time and for causing a position and a size of the detecting area on said image sensing plane to follow the variation of the object image in the second period; and (E) focus detecting means for detecting a focus state in the first period on the basis of said image signal corresponding to the detecting area.
Claim 12
Dependent Claim
144 words
A video camera device, comprising: (A) image sensing means for photoelectrically converting an object image formed on an image sensing plane to produce and output an image signal; (B) area setting means for setting detecting areas on said image sensing plane; (C) detecting means for detecting a variation of the object image in a first period of time; (D) control means for controlling said area setting means in accordance with an output of said detecting means in a second period of time longer than the first period of time and for causing a position and a size of the detecting area on said image sensing plane to follow the variation of the object image in the second period; and (E) focus detecting means for detecting a focus state in the first period on the basis of said image signal corresponding to the detecting area.
Claim 13
Dependent Claim
40 words
A device according to claim 9, wherein said detecting means is arranged to detect a difference of levels of a high frequency component of a luminance signal in said image signal between the inside and outside of the detecting area.
Claim 14
Dependent Claim
53 words
A device according to claim 10, wherein said control means is arranged to change a size of the detecting area so that a difference of level of the high frequency component between the inside and the outside of the detecting area becomes maximum, in respect to the respective ones of said detecting areas.
Claim 15
Dependent Claim
46 words
A device according to claim 10, wherein said focus detecting means is arranged to adopt the detecting area where the difference of level of the high frequency component between the inside and outside becomes maximum among said plurality of detecting areas, as a focus detecting area.
Claim 16
Dependent Claim
135 words
A video processing device, comprising: (A) imaging means for producing and outputting an image signal; (B) area setting means for shiftably setting a processing area in an image plane; (C) detecting means for detecting a variation of an object image on the basis of a variation of a predetermined signal component in said image signal in a first period of time; (D) control means for controlling said area setting means in accordance with an output of said detecting means and for changing a position and a size of said processing area on said image plane, following the change of the object image in a second period of, time longer than the first period; and (E) processing means for performing a predetermined process on the image signal corresponding to the processing area in the first period.
Claim 17
Dependent Claim
135 words
A video processing device, comprising: (A) imaging means for producing and outputting an image signal; (B) area setting means for shiftably setting a processing area in an image plane; (C) detecting means for detecting a variation of an object image on the basis of a variation of a predetermined signal component in said image signal in a first period of time; (D) control means for controlling said area setting means in accordance with an output of said detecting means and for changing a position and a size of said processing area on said image plane, following the change of the object image in a second period of, time longer than the first period; and (E) processing means for performing a predetermined process on the image signal corresponding to the processing area in the first period.
Claim 18
Dependent Claim
44 words
A device according to claim 13, wherein said processing means is focusing control means for detecting a focus state on the basis of the image signal corresponding to the inside of said processing area and for driving a focusing lens to an in-focus point.
Claim 19
Dependent Claim
23 words
A device according to claim 14, wherein said area setting means is capable of setting a plurality of processing areas having different sizes.
Claim 20
Dependent Claim
192 words
A video processing method, comprising: (A) area setting step for setting a plurality of work areas for measuring a position and/or size of an object image on a image plane; (B) detecting step for detecting a variation of the object image on the basis of a variation of predetermined signal components in an image signal in respect of an inner and outer part of the respective ones of said plurality of work areas in a first period of time; (C) control step for controlling a process of said area setting step in accordance with an output of said detecting step and for measuring the position and/or size of the object image by causing the positions and/or sizes of said plurality of work areas on said image plane to follow the variation of the object image, to independently change the work areas, respectively in the first period of time; and (D) processing area setting step for setting in a second period of time longer than the first period of time a processing area at a position of the work area where the predetermined signal component becomes maximum among said plurality of work areas.
Claim 21
Dependent Claim
192 words
A video processing method, comprising: (A) area setting step for setting a plurality of work areas for measuring a position and/or size of an object image on a image plane; (B) detecting step for detecting a variation of the object image on the basis of a variation of predetermined signal components in an image signal in respect of an inner and outer part of the respective ones of said plurality of work areas in a first period of time; (C) control step for controlling a process of said area setting step in accordance with an output of said detecting step and for measuring the position and/or size of the object image by causing the positions and/or sizes of said plurality of work areas on said image plane to follow the variation of the object image, to independently change the work areas, respectively in the first period of time; and (D) processing area setting step for setting in a second period of time longer than the first period of time a processing area at a position of the work area where the predetermined signal component becomes maximum among said plurality of work areas.
Claim 22
Dependent Claim
30 words
A method according to claim 16, further comprising correcting step for correcting the difference of levels of the predetermined signal component based on difference of sizes of said work areas.
Claim 23
Dependent Claim
36 words
A method according to claim 16, wherein said control step performs to shift said plurality of work areas so that a difference of luminance between the inside and the outside of each work area becomes maximum.
Claim 24
Dependent Claim
41 words
A method according to claim 16, wherein said processing area setting step adopts the work area where the difference of levels of the high frequency component between the inside and the outside of the area becomes maximum, as the processing area.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-07-11 | 2004-01-10 | 2004-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-07-11 | 2008-01-10 | 2008-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-07-11 | 2012-01-10 | 2012-07-11 | $7700.00 | Window Closed / Lapsed |