US4992855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image pickup apparatus with white balance control based on ambient light flicker
Assignee: Canon Inc
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Filing: 1989-08-03
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Granted: 1991-02-12
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Expires: 2009-08-03
Abstract
Abstract An image pickup apparatus includes image pickup circuitry for producing an image signal in response to a received image. Detecting circuitry is provided for detecting (1) a phase of a flicker component associated with a light source, and (2) a relationship between the detected phase of the flicker component and the timing of producing the image pickup signal by the image pickup circuitry. A control circuit is provided for controlling a white balance of the output of the image pickup circuitry based on the output of the detection circuitry.
Inventors
- 👤 Masahiro Takei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:55
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/70; H04N23/80; H04N23/84; H04N23/88
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
87 words
An image pickup apparatus comprising: image pickup means for producing an image signal in response to a received image; detecting means for detecting (1) a phase of a flicker component associated with a light source, and (2) a relationship between the detected phase of the flicker component and a timing of producing the image pickup signal by said image pickup means; and control means for controlling a white balance of the output of said image pickup means based on the phase relationship detected by said detection means.
Claim 2
Dependent Claim
87 words
An image pickup apparatus comprising: image pickup means for producing an image signal in response to a received image; detecting means for detecting (1) a phase of a flicker component associated with a light source, and (2) a relationship between the detected phase of the flicker component and a timing of producing the image pickup signal by said image pickup means; and control means for controlling a white balance of the output of said image pickup means based on the phase relationship detected by said detection means.
Claim 3
Dependent Claim
32 words
Apparatus according to claim 1 wherein said detection means includes a sensing element for producing an output signal which varies in correspondence to the change in color temperature of the light source.
Claim 4
Dependent Claim
30 words
Apparatus according to claim 2 wherein said sensing element includes a light sensor which is responsive to the change in luminosity of the light source correlated to the color temperature.
Claim 5
Dependent Claim
46 words
Apparatus according to claim 1 wherein said control means includes: timing signal generation means for generating timing signals in accordance with the detected phase relationship; and means for applying each of said timing signals to control the timing of image pickup by said image pickup means.
Claim 6
Dependent Claim
23 words
Apparatus according to claim 1 wherein said control means includes means for adjusting a period of image pickup by said image pickup means.
Claim 7
Dependent Claim
94 words
An image pickup apparatus comprising: image pickup means for producing an image signal in response to a received image; detecting means for detecting a flicker component and its phase associated with a light source; first control means for controlling said image pickup means for producing the image signal in accordance with the detected phase of the flicker component; and second control means for controlling, when the flicker component is detected by said detecting means, a white balance of the output of said image pickup means based at least on predetermined white balance control information.
Claim 8
Dependent Claim
94 words
An image pickup apparatus comprising: image pickup means for producing an image signal in response to a received image; detecting means for detecting a flicker component and its phase associated with a light source; first control means for controlling said image pickup means for producing the image signal in accordance with the detected phase of the flicker component; and second control means for controlling, when the flicker component is detected by said detecting means, a white balance of the output of said image pickup means based at least on predetermined white balance control information.
Claim 9
Dependent Claim
32 words
Apparatus according to claim 6 wherein said detection means includes a sensing element for producing an output signal which varies in correspondence to a change in color temperature of the light source.
Claim 10
Dependent Claim
30 words
Apparatus according to claim 7 wherein said sensing element includes a light sensor which is responsive to a change in luminosity of the light source correlated to the color temperature.
Claim 11
Dependent Claim
41 words
Apparatus according to claim 6 wherein said control means includes: timing signal generation means for generating timing signals having a predetermined cycle; and means for applying said timing signals to control the timing of image pickup by said image pickup means.
Claim 12
Dependent Claim
20 words
Apparatus according to claim 6 further comprising means for adjusting a period of image pickup by said image pickup means.
Claim 13
Dependent Claim
22 words
Apparatus according to claim 6 wherein said first control means controls a start timing of image pickup by said image pickup means.
Claim 14
Dependent Claim
26 words
An image pickup apparatus according to claim 6 wherein said predetermined white balance control information corresponds to a color temperature of a typical flicker light source.
Claim 15
Dependent Claim
28 words
Apparatus according to claim 6 wherein said second control means compensates the white balance in accordance with a level of the flicker component associated with the light source.
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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) | 1994-02-11 | 1994-08-13 | 1995-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-11 | 1998-08-13 | 1999-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-11 | 2002-08-13 | 2003-02-12 | $7700.00 | Window Closed / Lapsed |