US6693673B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital camera for adjusting charge accumulation time in response to object distance
Assignee: Minolta Co Ltd
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Filing: 1999-07-27
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Granted: 2004-02-17
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Expires: 2019-07-27
Abstract
Abstract In a digital camera, when flash shooting is performed, a maximum distance at which a subject can be illuminated to appropriate brightness is calculated based on the guide number of a flash and the open aperture value of an aperture stop, and the distance to the subject measured is compared with the maximum distance. If the distance to the subject is equal to or shorter than the maximum distance, the exposure time is set at a predetermined value, and the amount of the flash light emitted is controlled based on the amount of the light reflected from the subject, and white balance of the taken image is adjusted in accordance with the color characteristics of the flash light. If the distance to the subject is greater than the maximum distance, the exposure time is set to be longer than the predetermined value in order to use a larger amount of ambient light to illuminate the subject, and white balance of the taken image is adjusted in accordance with the color characteristics of the ambient light.
Inventors
- 👤 Toshiyuki Tanaka
- 👤 Toshihiro Hamamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:52
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/70; H04N23/72
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
101 words
A digital camera comprising: a photoelectric conversion device for sensing light from a subject to generate image data of the subject; a flash for emitting light to illuminate the subject; and a time setter for setting, when shooting is performed using the light emitted by the flash, a photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion in accordance with a distance to the subject, wherein the time setter sets the photoelectric conversion time to be equal to a predetermined length of time when the distance to the subject is equal to or shorter than a predetermined distance.
Claim 2
Dependent Claim
101 words
A digital camera comprising: a photoelectric conversion device for sensing light from a subject to generate image data of the subject; a flash for emitting light to illuminate the subject; and a time setter for setting, when shooting is performed using the light emitted by the flash, a photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion in accordance with a distance to the subject, wherein the time setter sets the photoelectric conversion time to be equal to a predetermined length of time when the distance to the subject is equal to or shorter than a predetermined distance.
Claim 3
Dependent Claim
39 words
A digital camera as claimed in claim 1 , wherein the time setter sets the photoelectric conversion time to be longer than the predetermined length of time when the distance to the subject is longer than the predetermined distance.
Claim 4
Dependent Claim
25 words
A digital camera as claimed in claim 1 , wherein the predetermined length of time is determined based on a guide number of the flash.
Claim 5
Dependent Claim
29 words
A digital camera as claimed in claim 1 , further comprising: a balance adjuster for performing white balance adjustment on the image data generated by the photoelectric conversion device.
Claim 6
Dependent Claim
43 words
A digital camera as claimed in claim 4 , wherein the balance adjuster performs white balance adjustment based on color characteristics of the light emitted by the flash when the distance to the subject is equal to or shorter than a predetermined distance.
Claim 7
Dependent Claim
36 words
A digital camera as claimed in claim 5 , wherein the balance adjuster performs white balance adjustment based on color characteristics of ambient light when the distance to the subject is longer than the predetermined distance.
Claim 8
Dependent Claim
67 words
A digital camera as claimed in claim 1 , wherein, whether shooting is performed using light emitted by the flash, ambient light, or a combination thereof, the predetermined length of time is a maximum handshake-free period, wherein the maximum hand-shake-free period is a maximum photoelectric conversion time that does not allow a shake of a hand to cause a substantially noticeable distortion of the subject image data.
Claim 9
Dependent Claim
72 words
A digital camera as claimed in claim 1 , further comprising: a checker for checking an exposure condition of the subject image data; an amplification circuit; and a gain setter for setting a gain of the amplification circuit, wherein when the checker recognizes an under exposure condition, the gain and the photoelectric conversion time are respectively set in such a way that the photoelectric conversion time multiplied by the gain remains constant.
Claim 10
Dependent Claim
228 words
A digital camera comprising: a photoelectric conversion device for sensing light from a subject to generate image data of the subject; a flash for emitting light to illuminate the subject; a first time setter for setting, when shooting is performed using the light emitted by the flash, a photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion to be equal to a predetermined length of time when a distance to the subject is equal to or shorter than a predetermined distance that corresponds to a guide number of the flash; a second time setter for setting, when shooting is performed using the light emitted by the flash, the photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion to be longer than the predetermined length of time when the distance to the subject is longer than the predetermined distance; a first balance adjuster for performing white balance adjustment on the image data generated by the photoelectric conversion device based on color characteristics of the light emitted by the flash when the distance to the subject is equal to or shorter than the predetermined distance; and a second balance adjuster for performing white balance adjustment on the image data generated by the photoelectric conversion device based on color characteristics of ambient light when the distance to the subject is longer than the predetermined distance.
Claim 11
Dependent Claim
228 words
A digital camera comprising: a photoelectric conversion device for sensing light from a subject to generate image data of the subject; a flash for emitting light to illuminate the subject; a first time setter for setting, when shooting is performed using the light emitted by the flash, a photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion to be equal to a predetermined length of time when a distance to the subject is equal to or shorter than a predetermined distance that corresponds to a guide number of the flash; a second time setter for setting, when shooting is performed using the light emitted by the flash, the photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion to be longer than the predetermined length of time when the distance to the subject is longer than the predetermined distance; a first balance adjuster for performing white balance adjustment on the image data generated by the photoelectric conversion device based on color characteristics of the light emitted by the flash when the distance to the subject is equal to or shorter than the predetermined distance; and a second balance adjuster for performing white balance adjustment on the image data generated by the photoelectric conversion device based on color characteristics of ambient light when the distance to the subject is longer than the predetermined distance.
Claim 12
Dependent Claim
114 words
A digital camera that shoots an image by means of a photoelectric conversion device and that is capable of performing flash shooting by emitting flash light to illuminate a subject, during photoelectric conversion, wherein, in flash shooting, when the subject lies within a distance range in which the flash light can illuminate the subject with predetermined brightness, a photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion is set to be equal to a predetermined length of time, and, when the subject lies outside the distance range, the photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion is set to be longer than the predetermined length of time.
Claim 13
Dependent Claim
114 words
A digital camera that shoots an image by means of a photoelectric conversion device and that is capable of performing flash shooting by emitting flash light to illuminate a subject, during photoelectric conversion, wherein, in flash shooting, when the subject lies within a distance range in which the flash light can illuminate the subject with predetermined brightness, a photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion is set to be equal to a predetermined length of time, and, when the subject lies outside the distance range, the photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion is set to be longer than the predetermined length of time.
Claim 14
Dependent Claim
96 words
A digital camera as claimed in claim 10 , wherein, when flash shooting is performed with the photoelectric conversion time of the photoelectric conversion device set to be equal to the predetermined length of time, the image shot is subjected to white balance adjustment performed based on color characteristics of the flash light, and, when flash shooting is performed with the photoelectric conversion time of the photoelectric conversion device set to be longer than the predetermined length of time, the image shot is subjected to white balance adjustment performed based on color characteristics of ambient light.
Claim 15
Independent Claim
116 words
A method of operating a digital camera to generate image data of a subject, the method comprising the steps of: performing photoelectric conversion using a photoelectric conversion device for sensing light from the subject in order to generate the image data of the subject; emitting light from a flash to illuminate the subject; and when shooting is performed using the light emitted by the flash, setting a photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion in accordance with a distance to the subject, wherein when the distance to the subject is equal to or shorter than a predetermined distance, the photoelectric conversion time is set equal to a predetermined length of time.
Claim 16
Independent Claim
116 words
A method of operating a digital camera to generate image data of a subject, the method comprising the steps of: performing photoelectric conversion using a photoelectric conversion device for sensing light from the subject in order to generate the image data of the subject; emitting light from a flash to illuminate the subject; and when shooting is performed using the light emitted by the flash, setting a photoelectric conversion time for which the photoelectric conversion device performs photoelectric conversion in accordance with a distance to the subject, wherein when the distance to the subject is equal to or shorter than a predetermined distance, the photoelectric conversion time is set equal to a predetermined length of time.
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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) | 2007-02-16 | 2007-08-18 | 2008-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-02-16 | 2011-08-18 | 2012-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-02-16 | 2015-08-18 | 2016-02-17 | $7700.00 | Window Closed / Lapsed |