US4477171A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic flash system
Assignee: Canon Inc
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Filing: 1982-07-28
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Granted: 1984-10-16
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Expires: 2002-07-28
Abstract
Abstract There is disclosed an electronic flash system having a diaphragm which is operated on the basis of an aperture control signal from an electronic flash device. A light sensitive element position in the camera system produces an electrical signal representing the amount of flash light passed through the aforesaid diaphragm of the adjusted aperture size. A circuit for controlling the amount of flash light emitted from the flash device controls the amount of flash light based on the electrical signal.
Inventors
- 👤 Masanori Yamada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:09
CPC Classifications
G; G03; G03B; G03B15/00; G03B15/02; G03B15/03; G03B15/05; G03B7/00; G03B7/16; G03B2215/00; G03B2215/05
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
212 words
A combination of a camera selectively attachable with a plurality of interchangeable lenses and an electronic flash device detachable from said camera, comprising: (a) flash emitting means for emitting light to illuminate an object to be photographed; (b) diaphragm means provided in each of said lenses, dynamic ranges of at least two of the diaphragm means being different from each other; (c) diaphragm control means for controlling an aperture size of said diaphragm means of the attached lens on the basis of one of a plurality of aperture value signals to be applied from the outside of said camera; (d) means provided in said electronic flash device and for selectively producing said aperture value signals to be applied to said diaphragm control means, one of the aperture value signals being out of the dynamic range of at least one of said lenses; (e) light sensitive means responsive to the reflected light from the object after being passed through said diaphragm means controlled by said diaphragm control means and for generating a control signal when an amount of the reflected light has reached a predetermined level; and (f) light control means for terminating emission of the light from the flash emitting means in response to the control signal from said light sensitive means.
Claim 2
Dependent Claim
212 words
A combination of a camera selectively attachable with a plurality of interchangeable lenses and an electronic flash device detachable from said camera, comprising: (a) flash emitting means for emitting light to illuminate an object to be photographed; (b) diaphragm means provided in each of said lenses, dynamic ranges of at least two of the diaphragm means being different from each other; (c) diaphragm control means for controlling an aperture size of said diaphragm means of the attached lens on the basis of one of a plurality of aperture value signals to be applied from the outside of said camera; (d) means provided in said electronic flash device and for selectively producing said aperture value signals to be applied to said diaphragm control means, one of the aperture value signals being out of the dynamic range of at least one of said lenses; (e) light sensitive means responsive to the reflected light from the object after being passed through said diaphragm means controlled by said diaphragm control means and for generating a control signal when an amount of the reflected light has reached a predetermined level; and (f) light control means for terminating emission of the light from the flash emitting means in response to the control signal from said light sensitive means.
Claim 3
Dependent Claim
28 words
The combination according to claim 1, wherein said light sensitive means includes a light sensitive element responsive to a light reflective by a film provided in said camera.
Claim 4
Dependent Claim
19 words
The combination according to claim 1, wherein said light sensitive element is provided in a body of the camera.
Claim 5
Dependent Claim
184 words
A combination of a camera selectively attachable with a plurality of interchangeable lenses and an electronic flash device, comprising: (a) flash emitting means for emitting light to illuminate an object to be photographed; (b) diaphragm means provided in each of said lenses, dynamic ranges of at least two of the diaphragm means being different from each other; (c) diaphragm control means for controlling an aperture size of said diaphragm means of the attached lens on the basis of one of a plurality of electrical signals to be applied from the outside of said camera; (d) means provided in said electronic flash device and for selectively producing said electrical signals to decide said aperture size; (e) light sensitive means responsive to the reflected light from the object after being passed through said diaphragm means controlled by said diaphragm control means and for generating a control signal when an amount of the reflected light has reached a predetermined level; and (f) light control means for terminating emission of the light from the flash emitting means in response to the control signal from said light sensitive means.
Claim 6
Dependent Claim
184 words
A combination of a camera selectively attachable with a plurality of interchangeable lenses and an electronic flash device, comprising: (a) flash emitting means for emitting light to illuminate an object to be photographed; (b) diaphragm means provided in each of said lenses, dynamic ranges of at least two of the diaphragm means being different from each other; (c) diaphragm control means for controlling an aperture size of said diaphragm means of the attached lens on the basis of one of a plurality of electrical signals to be applied from the outside of said camera; (d) means provided in said electronic flash device and for selectively producing said electrical signals to decide said aperture size; (e) light sensitive means responsive to the reflected light from the object after being passed through said diaphragm means controlled by said diaphragm control means and for generating a control signal when an amount of the reflected light has reached a predetermined level; and (f) light control means for terminating emission of the light from the flash emitting means in response to the control signal from said light sensitive means.
References Cited (Backward Citations)
US3726197A
Cited
US4382666A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-16 | 1988-04-16 | 1988-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-16 | 1992-04-16 | 1992-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-16 | 1996-04-16 | 1996-10-16 | $7700.00 | Window Closed / Lapsed |