US4542974A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flash photography apparatus
Assignee: Canon Inc
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Filing: 1984-06-28
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Granted: 1985-09-24
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Expires: 2004-06-28
Abstract
Abstract In the disclosed flash unit, a preliminary flash for evaluating a proper exposure precedes a main flash. A flash exposure control apparatus respond to tilting of the flash's head after a preliminary flash to present a warning signal, or to renew the preliminary flash and thereby to readjust the aperture to the new exposure condition.
Inventors
- 👤 Ryoichi Yoshikawa
- 👤 Kouichi Ohmori
- 👤 Isao Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:52
CPC Classifications
G; G03; G03B; G03B15/00; G03B15/02; G03B15/03; G03B15/05; G03B2215/00; G03B2215/05; G03B2215/0514; G03B2215/0517; G03B2215/0525; G03B2215/0528
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
95 words
A flash photography apparatus having a main body, in which an exposure factor is determined with a preliminary firing and then a main firing is produced, comprising: (a) a head portion changeable in position relative to the main body, said head portion being provided with light emitting means; and (b) a detector circuit for detecting the change of position of said head portion, said detector circuit producing a detection signal and including warning means responsive to said detection signal for performing a warning operation when the head portion changes its position after the preliminary firing.
Claim 2
Dependent Claim
95 words
A flash photography apparatus having a main body, in which an exposure factor is determined with a preliminary firing and then a main firing is produced, comprising: (a) a head portion changeable in position relative to the main body, said head portion being provided with light emitting means; and (b) a detector circuit for detecting the change of position of said head portion, said detector circuit producing a detection signal and including warning means responsive to said detection signal for performing a warning operation when the head portion changes its position after the preliminary firing.
Claim 3
Dependent Claim
132 words
A flash photography apparatus having a main body, in which an exposure factor is determined by a preliminary firing and then a main firing is carried out, comprising: (a) a head portion changeable in position relative to the main body, said head portion being provided with light emitting means; (b) a measuring circuit receptive of the reflection of preliminary firing flash light from an object to be photographed for determining the exposure factor, said measuring circuit having a photosensitive element positioned on the main body; and (c) a detector circuit for detecting the change of position of said head portion, said detector circuit producing a detection signal and including warning means responsive to said detection signal for performing a warning operation when the head portion changes its position after the preliminary firing.
Claim 4
Dependent Claim
132 words
A flash photography apparatus having a main body, in which an exposure factor is determined by a preliminary firing and then a main firing is carried out, comprising: (a) a head portion changeable in position relative to the main body, said head portion being provided with light emitting means; (b) a measuring circuit receptive of the reflection of preliminary firing flash light from an object to be photographed for determining the exposure factor, said measuring circuit having a photosensitive element positioned on the main body; and (c) a detector circuit for detecting the change of position of said head portion, said detector circuit producing a detection signal and including warning means responsive to said detection signal for performing a warning operation when the head portion changes its position after the preliminary firing.
Claim 5
Dependent Claim
131 words
A flash photography apparatus having a main body in which an exposure factor is determined by a preliminary firing and then a main firing is carried out, comprising: (a) a head portion changeable in position relative to the main body, said head portion having light emitting means; (b) a detector circuit for detecting a change of position of said head portion relative to the main body; (c) a preliminary firing operation control circuit for causing said light emitting means to carry out a preliminary firing; and (d) a warning signal forming circuit for receiving an actuating signal from said preliminary firing operation control circuit and a detection signal from said detector circuit and responsive to simultaneous occurrence of actuating and detection signals for causing warning means to perform a warning operation.
Claim 6
Dependent Claim
131 words
A flash photography apparatus having a main body in which an exposure factor is determined by a preliminary firing and then a main firing is carried out, comprising: (a) a head portion changeable in position relative to the main body, said head portion having light emitting means; (b) a detector circuit for detecting a change of position of said head portion relative to the main body; (c) a preliminary firing operation control circuit for causing said light emitting means to carry out a preliminary firing; and (d) a warning signal forming circuit for receiving an actuating signal from said preliminary firing operation control circuit and a detection signal from said detector circuit and responsive to simultaneous occurrence of actuating and detection signals for causing warning means to perform a warning operation.
Claim 7
Dependent Claim
99 words
A flash photography apparatus having a main body, in which an exposure factor is determined by a preliminary firing and then a main firing is carried out comprising: (a) a head portion changeable in position relative to the main body, said head portion having light emitting means; and (b) a detector circuit for detecting a change of position of said head portion, said detector circuit being responsive to detection of the fact that after the preliminary firing, said head portion has changed position, for producing a detection signal to cause said light emitting means to perform another preliminary firing.
Claim 8
Dependent Claim
99 words
A flash photography apparatus having a main body, in which an exposure factor is determined by a preliminary firing and then a main firing is carried out comprising: (a) a head portion changeable in position relative to the main body, said head portion having light emitting means; and (b) a detector circuit for detecting a change of position of said head portion, said detector circuit being responsive to detection of the fact that after the preliminary firing, said head portion has changed position, for producing a detection signal to cause said light emitting means to perform another preliminary firing.
Claim 9
Dependent Claim
137 words
A flash photography apparatus having a main body, in which an exposure factor is determined by a preliminary firing and then a main firing is carried out, comprising: (a) a head portion changeable in position relative to the main body, said head portion being provided with light emitting means; (b) a detector circuit for detecting a change of position of said head portion relative to the main body; (c) a preliminary firing operation control circuit for causing said light emitting means to carry out a preliminary firing; and (d) a signal forming circuit for receiving an actuating signal from said preliminary firing operation control circuit and a detection signal from said detector circuit and responsive to simultaneous occurrence of the actuating and detection signals for producing a signal for again actuating said preliminary firing operation control circuit.
Claim 10
Dependent Claim
137 words
A flash photography apparatus having a main body, in which an exposure factor is determined by a preliminary firing and then a main firing is carried out, comprising: (a) a head portion changeable in position relative to the main body, said head portion being provided with light emitting means; (b) a detector circuit for detecting a change of position of said head portion relative to the main body; (c) a preliminary firing operation control circuit for causing said light emitting means to carry out a preliminary firing; and (d) a signal forming circuit for receiving an actuating signal from said preliminary firing operation control circuit and a detection signal from said detector circuit and responsive to simultaneous occurrence of the actuating and detection signals for producing a signal for again actuating said preliminary firing operation control circuit.
Claim 11
Dependent Claim
75 words
A flash photography apparatus of the type in which an exposure factor is determined with a preliminary flash and then a main flash is produced, comprising: (a) illumination determining means for determining the illumination of an object by the main flash, and (b) detection means for generating a warning signal to cause warning means to perform a warning operation when the illumination determined by the illumination determining means changes after the preliminary flash is done.
Claim 12
Dependent Claim
75 words
A flash photography apparatus of the type in which an exposure factor is determined with a preliminary flash and then a main flash is produced, comprising: (a) illumination determining means for determining the illumination of an object by the main flash, and (b) detection means for generating a warning signal to cause warning means to perform a warning operation when the illumination determined by the illumination determining means changes after the preliminary flash is done.
Claim 13
Dependent Claim
68 words
A flash photography apparatus of the type in which an exposure factor is determined with a preliminary flash and then a main flash is produced, comprising: (a) illumination determining means for determining the illumination of an object by the main flash, and (b) a control circuit for performing another preliminary flash when the illumination determined by the illumination determining means changes after the first preliminary flash is done.
Claim 14
Dependent Claim
68 words
A flash photography apparatus of the type in which an exposure factor is determined with a preliminary flash and then a main flash is produced, comprising: (a) illumination determining means for determining the illumination of an object by the main flash, and (b) a control circuit for performing another preliminary flash when the illumination determined by the illumination determining means changes after the first preliminary flash is done.
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) | 1988-09-23 | 1989-03-25 | 1989-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-23 | 1993-03-25 | 1993-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-23 | 1997-03-25 | 1997-09-24 | $7700.00 | Window Closed / Lapsed |