US4825293A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sensitivity compensating method for solid-state image pickup element used in electronic still camera
Assignee: Fujifilm Holdings Corp
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Filing: 1987-10-16
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Granted: 1989-04-25
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Expires: 2007-10-16
Abstract
Abstract A method for compensating changes which would otherwise be produced in a video output signal when the shutter speed exceeds a certain value, even though the same light level of the received image is maintained on the image pickup. In one embodiment, the shutter speed and/or aperture setting are adjusted to compensate. The amplification factor of the output video signal can also be adjusted. In other embodiments, gamma correction is effected separately for each primary color signal to compensate for the changes which affect the color signals in different amounts as the shutter speed is increased.
Inventors
- 👤 Kiyotaka Kobayashi
- 👤 Masatoshi Tabei
- 👤 Madoka Arashi
- 👤 Yuzo Mizobuchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:40
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/70; H04N23/72
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
107 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in said output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal.
Claim 2
Dependent Claim
107 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in said output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal.
Claim 3
Dependent Claim
32 words
The photographing method of claim 1, wherein said step of compensating comprises controlling at least one of said iris and said shutter to increase the level of light received on said pickup.
Claim 4
Dependent Claim
143 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, said method comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in said output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal, wherein said step of compensating comprises compensating a gamma characteristic separately for each color in said video signal so as to maintain a constant relationship with respect to said image received on said pickup.
Claim 5
Dependent Claim
143 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, said method comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in said output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal, wherein said step of compensating comprises compensating a gamma characteristic separately for each color in said video signal so as to maintain a constant relationship with respect to said image received on said pickup.
Claim 6
Dependent Claim
44 words
The photographing method of claim 3, wherein the colors contained in said video signal are the three primary colors, and wherein, in said step of compensating said gamma characteristic, a correction is effected for each color in an amount dependent upon said shutter speed.
Claim 7
Dependent Claim
46 words
The photographing method of claim 3, wherein the colors contained in said video signal are complements of the three primary colors, and wherein, in said step of compensating said gamma characteristic, a correction is effected of each color in an amount dependent upon said shutter speed.
Claim 8
Dependent Claim
37 words
The photographing method of claim 3, further comprising the step of producing a luminance signal in response to the gamma-corrected color signals, and amplifying said luminance signal with a gain determined in response to said shutter speed.
Claim 9
Dependent Claim
135 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, said method comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in said output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal, wherein said step of compensating comprises increasing an amplification factor of said video output signal in response to an amount of light received on said pickup.
Claim 10
Dependent Claim
135 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, said method comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in said output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal, wherein said step of compensating comprises increasing an amplification factor of said video output signal in response to an amount of light received on said pickup.
Claim 11
Dependent Claim
142 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, said video output signal including a color carrier signal modulated with image information, said method comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in an output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal, wherein said step of compensating comprises adjusting an amplitude of said color carrier signal in response to said shutter speed.
Claim 12
Dependent Claim
142 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, said video output signal including a color carrier signal modulated with image information, said method comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in an output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal, wherein said step of compensating comprises adjusting an amplitude of said color carrier signal in response to said shutter speed.
Claim 13
Dependent Claim
153 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, said method comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in said output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal, wherein said step of compensating comprises maintaining a first relationship between said shutter speed and aperture value at shutter speeds below said predetermined value and maintaining a second relationship between said shutter speed and said aperture value at shutter speeds above said predetermined value.
Claim 14
Dependent Claim
153 words
A photographing method for a camera having an iris for setting an aperture setting value, a shutter, a solid-state image pickup for sensing an input image received by said pickup and for providing an output having an output level, and means for producing a video output signal in response to said output of said pickup, said method comprising the steps of: determining when a shutter speed of said shutter exceeds a predetermined value; and compensating a drop in said output level of said pickup which occurs when said shutter speed exceeds said predetermined value so as to maintain a predetermined relationship between said image and said video output signal, wherein said step of compensating comprises maintaining a first relationship between said shutter speed and aperture value at shutter speeds below said predetermined value and maintaining a second relationship between said shutter speed and said aperture value at shutter speeds above said predetermined value.
References Cited (Backward Citations)
US4739409A
Cited
US4695891A
Cited
USPTO Annuity & Maintenance Windows
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| 3.5 Years (Year 4) | 1992-04-24 | 1992-10-24 | 1993-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-24 | 1996-10-24 | 1997-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-24 | 2000-10-24 | 2001-04-25 | $7700.00 | Window Closed / Lapsed |