US6069659A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Strobe device that prevents the flicker of flashlight and flashing method thereof
Assignee: Olympus Corp
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Filing: 1997-06-03
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Granted: 2000-05-30
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Expires: 2017-06-03
Abstract
Abstract A strobe device and its flashing method for use with an electronic camera of the present invention are such that a preliminary flashlight to set the amount of light of the main flashing is received by a CCD 1, the amount of light of the main flashing is set on the basis of the signal from the CCD 1, the time interval between the preliminary flashing and the main flashing is set to a time that prevents the photographer from recognizing fluctuations in the luminance, and when the interval has exceeded the time, more than one flashing that has nothing to do with the setting of the amount of light of the main flashing is done between the preliminary flashing and the main flashing, thereby preventing the flicker of flashing that gives a sense of incongruity to the photographer.
Inventors
- 👤 Yukio Nakajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:03
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/70; H04N23/74
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
146 words
A strobe device comprising: preliminary flash projecting means for effecting preliminary flashing to set the amount of light of the main flashing by projecting supplementary light on a subject for photography; a two-dimensional imaging element for photoelectrically converting the light reflected from the subject which is illuminated by the preliminary flashing of said preliminary flash projecting means; amount-of-flashlight computing means for calculating the amount of light of the main flashing projected on the subject from the output of said two-dimensional imaging element; flashing control means for setting the amount of light of said main flashing on the basis of the calculation result produced by said amount-of-light computing means; and means for setting the interval between said preliminary flashing and said main flashing at such a time as prevents the naked eye from recognizing fluctuations in the luminance existing between said preliminary flashing and said main flashing.
Claim 2
Dependent Claim
146 words
A strobe device comprising: preliminary flash projecting means for effecting preliminary flashing to set the amount of light of the main flashing by projecting supplementary light on a subject for photography; a two-dimensional imaging element for photoelectrically converting the light reflected from the subject which is illuminated by the preliminary flashing of said preliminary flash projecting means; amount-of-flashlight computing means for calculating the amount of light of the main flashing projected on the subject from the output of said two-dimensional imaging element; flashing control means for setting the amount of light of said main flashing on the basis of the calculation result produced by said amount-of-light computing means; and means for setting the interval between said preliminary flashing and said main flashing at such a time as prevents the naked eye from recognizing fluctuations in the luminance existing between said preliminary flashing and said main flashing.
Claim 3
Dependent Claim
96 words
A strobe device according to claim 1, wherein when the time interval between said preliminary flashing and said main flashing has exceeded said time that prevents the naked eye from recognizing fluctuations in the luminance, said preliminary flash projecting means effects flashing once or more times that has nothing to do with the setting of the amount of light of the main flashing, during the interval between the preliminary flashing and the main flashing to force the setting time to lie in the time interval that prevents the naked eye from recognizing fluctuations in the luminance.
Claim 4
Dependent Claim
31 words
A strobe device according to claim 1, wherein the interval between said preliminary flashing and said main flashing is within a time range which is an inverse of (Critical Fusion Frequency).
Claim 5
Dependent Claim
48 words
A strobe device according to claim 1, wherein the flashing for the setting to prevent the naked eye from recognizing fluctuations in the luminance existing between said preliminary flashing and said main flashing corresponds to the period for reading the photoelectrically converted signal from said two-dimensional imaging element.
Claim 6
Dependent Claim
24 words
A strobe device according to claim 4, wherein said preliminary flashing includes more than one preliminary flashing each differing in the amount of light.
Claim 7
Dependent Claim
30 words
A strobe device according to claim 5, wherein said more than one preliminary flashing increases in the amount of flashlight as the number of repetitions of the preliminary flashing increases.
Claim 8
Dependent Claim
26 words
A strobe device according to claim 6, wherein said amount of flashlight increases in steps of the n-th power of 2 (n is an integer) times.
Claim 9
Dependent Claim
30 words
A strobe device according to claim 5, wherein of said more than one preliminary flashing, the one suitable to obtain a proper image signal is chosen for the main flashing.
Claim 10
Dependent Claim
41 words
A strobe device according to claim 2, wherein said flashing that prevents the naked eye from recognizing fluctuations in the luminance existing between said preliminary flashing and said main flashing, is smaller in the amount of flashlight than said preliminary flashing.
Claim 11
Dependent Claim
133 words
A strobe device comprising: preliminary flash projecting means for preliminarily flashing to set the amount of light of the main flashing, by projecting supplementary flashlight on a subject for photography; a two-dimensional imaging element for photoelectrically converting the light reflected from the subject which is illuminated by the preliminary flashing of said preliminary flash projecting means; amount-of-flashlight computing means for calculating the amount of light of the main flashing to be projected on the subject on the basis of the difference between a first output produced by said two-dimensional imaging element with preliminary flashing and a second output produced by said two-dimensional imaging element without preliminary flashing; and flashing control means for setting the amount of light of the main flashing on the basis of the calculation result from said amount-of-light computing means.
Claim 12
Dependent Claim
133 words
A strobe device comprising: preliminary flash projecting means for preliminarily flashing to set the amount of light of the main flashing, by projecting supplementary flashlight on a subject for photography; a two-dimensional imaging element for photoelectrically converting the light reflected from the subject which is illuminated by the preliminary flashing of said preliminary flash projecting means; amount-of-flashlight computing means for calculating the amount of light of the main flashing to be projected on the subject on the basis of the difference between a first output produced by said two-dimensional imaging element with preliminary flashing and a second output produced by said two-dimensional imaging element without preliminary flashing; and flashing control means for setting the amount of light of the main flashing on the basis of the calculation result from said amount-of-light computing means.
Claim 13
Dependent Claim
120 words
In a photographing method using strobe light as supplementary light to compensate for the shortage of steady light, a strobe flashing method for electronic cameras, comprising the steps of: effecting at least more than one preliminary flashing to determine the amount of light of the main flashing in a period of time that prevents the naked eye from feeling a flicker due to an afterimage effect, before the main flashing of the strobe light; causing an imaging element for taking a picture of an image to integrate the amount of light for the period including said preliminary flashing and to output the result; and determining the amount of light of the main flashing on the basis of the output result.
Claim 14
Dependent Claim
120 words
In a photographing method using strobe light as supplementary light to compensate for the shortage of steady light, a strobe flashing method for electronic cameras, comprising the steps of: effecting at least more than one preliminary flashing to determine the amount of light of the main flashing in a period of time that prevents the naked eye from feeling a flicker due to an afterimage effect, before the main flashing of the strobe light; causing an imaging element for taking a picture of an image to integrate the amount of light for the period including said preliminary flashing and to output the result; and determining the amount of light of the main flashing on the basis of the output result.
Claim 15
Dependent Claim
60 words
A strobe flashing method according to claim 11, further comprising the step of determining the amount of light of the main flashing on the basis of the relative relationship between a first integration result obtained by integrating only said steady light and a second integration result obtained by integrating the amount of light in the period including said preliminary flashing.
Claim 16
Dependent Claim
55 words
A strobe flashing method according to claim 11, further comprising the step of, when the interval between said preliminary flashing and said main flashing is longer than an inverse of CFF (Critical Fusion Frequency), effecting at least one dummy flashing in the interval to make the interval between one flashing and another smaller than CFF.
Claim 17
Dependent Claim
71 words
A strobe flashing method according to claim 11, further comprising the steps of: effecting said preliminary flashing a plurality of times, each differing in the amount of light; and setting a flashing time to give the amount of light of the main flashing on the basis of the relative relationship between the output results of the imaging element corresponding to each flashing and the output result of the steady light only.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-05-30 | 2003-11-29 | 2004-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-05-30 | 2007-11-29 | 2008-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-05-30 | 2011-11-29 | 2012-05-30 | $7700.00 | Window Closed / Lapsed |