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US5019894A Expired / Lapsed US ⏱️ 0.0 years remaining

White balance adjusting circuit

Assignee: Canon Inc
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Filing: 1990-10-03
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Granted: 1991-05-28
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Expires: 2010-10-03
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Abstract

Abstract A white balance adjusting circuit which detects the ratio of color components in an illumination light around an object, independently from an image sensing system, and controls the gain of each color signal coming from the image sensing system, characterized in that it comprises means for correcting a signal indicative of the ratio of color components according to the color signal, not gain-controlled, coming from the image sensing system.

Inventors

  • 👤 Teruo Hieda
  • 👤 Kenji Kyuma

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 14:44
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/80; H04N23/84; H04N23/88

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 114 words
An image sensing apparatus comprising: first control signal forming means for forming a first control signal to control the white balance of outputs of image sensing means, by using image signals provided by said image sensing means; second control signal forming means for forming a second control signal to control the white balance of outputs of said image sensing means, by using outputs of color temperature detecting means; and control means for controlling the white balance of outputs of said image sensing means by varying a combination of said first and second control signals in accordance with a ratio of color signals provided by said image sensing means and said color temperature detecting means.
Claim 2
Dependent Claim 114 words
An image sensing apparatus comprising: first control signal forming means for forming a first control signal to control the white balance of outputs of image sensing means, by using image signals provided by said image sensing means; second control signal forming means for forming a second control signal to control the white balance of outputs of said image sensing means, by using outputs of color temperature detecting means; and control means for controlling the white balance of outputs of said image sensing means by varying a combination of said first and second control signals in accordance with a ratio of color signals provided by said image sensing means and said color temperature detecting means.
Claim 3
Dependent Claim 19 words
An apparatus according to claim 1, wherein said color temperature detecting means includes a plurality of color sensor elements.
Claim 4
Dependent Claim 23 words
An apparatus according to claim 2, wherein said plurality of color sensor elements includes at least a red sensor and a blue sensor.
Claim 5
Dependent Claim 125 words
An image sensing apparatus comprising: first control signal forming means for forming a first control signal to control the white balance of outputs of image sensing means, by using image signals provided by said image sensing means; a zoom optical system for forming an optical image on said image sensing means at a variable magnification; second control signal forming means for forming a second control signal to control the white balance of outputs of said image sensing means, by using outputs of color temperature detecting means; and control means for controlling the white balance of outputs of said image sensing means by varying a combination of said first and second control signals in accordance with the variable magnification of zoom in said zoom optical system.
Claim 6
Dependent Claim 125 words
An image sensing apparatus comprising: first control signal forming means for forming a first control signal to control the white balance of outputs of image sensing means, by using image signals provided by said image sensing means; a zoom optical system for forming an optical image on said image sensing means at a variable magnification; second control signal forming means for forming a second control signal to control the white balance of outputs of said image sensing means, by using outputs of color temperature detecting means; and control means for controlling the white balance of outputs of said image sensing means by varying a combination of said first and second control signals in accordance with the variable magnification of zoom in said zoom optical system.
Claim 7
Dependent Claim 19 words
An apparatus according to claim 4, wherein said color temperature detecting means includes a plurality of color sensor elements.
Claim 8
Dependent Claim 23 words
An apparatus according to claim 5, wherein said plurality of color sensor elements include at least a red sensor and a blue sensor.

References Cited (Backward Citations)

US4931856A Cited
JPS60192485A Cited
JPS61245782A Cited
JPS61272500A Cited
JPS62279795A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-05-27 1994-11-26 1995-05-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-05-27 1998-11-26 1999-05-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-05-27 2002-11-26 2003-05-28 $7700.00 Window Closed / Lapsed

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