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US 4,047,194 AGranted
Camera system with means for automatically switching to flash operation
AssigneeCanon Kabushiki Kaisha
InventorsZenzo Nakamura, Takashi Uchiyama, Masanori Uchidoi, Tetsuya Taguchi, Hiroshi Aizawa, Tokuichi Tsunekawa
Life of this patent
Estimating the term…
Abstract
A camera system is composed of a flash and a camera in which the diaphragm and shutter time control as well as the indicating mechanism are automatically switched into a flash mode in response to the charge accumulation completion signal from the electronic flash discharge device.
Claims27
A flash camera system, comprising:
- A. a flash device, having:
- a. a flash discharge tube,
- b. energy accumulation means connected to said discharge tube for accumulating energy to energize the flash discharge tube,
- c. accumulation completion signal forming means connected to said energy accumulation means for forming an energy accumulation completion signal when the energy accumulated at said energy accumulation means reaches a prescribed level,
- d. diaphragm information forming means to form a diaphragm information signal corresponding to a constant diaphragm aperture value prescribed for flash photography, and
- e. a flash control circuit coupled to said discharge tube to control the amount of light from said flash discharge tube on the basis of data depending on the distance to an object, and
- B. a camera, including an objective having a diaphragm defining an exposure opening, and automatic means coupled to the diaphragm for setting the diaphragm aperture to the prescribed aperture value in response to the energy accumulation completion signal at a time of flash photography, said automatic means including;
- a. exposure opening control means coupled to said diaphragm to control the exposure opening,
- b. an exposure opening control circuit coupled to said exposure opening control means, said circuit having a flash control mode which controls the exposure opening control means based on said prescribed diaphragm aperture value information signal, and
- c. a designating circuit connected to said exposure opening control circuit and responding to said energy accumulation completion signal by forming a mode designation signal for setting said exposure opening control circuit to the flash control mode so that the exposure opening control circuit is automatically set to the flash control mode.
7 more elements
A flash camera system, comprising:
- A. a flash device, having:
- a. a flash discharge tube,
- b. energy accumulation means connected to said discharge tube for accumulating energy to energize the flash discharge tube,
- c. accumulation completion signal forming means connected to said energy accumulation means for forming an energy accumulation completion signal when the energy accumulated at said energy accumulation means reaches a prescribed level,
- d. diaphragm information forming means to form a diaphragm information signal corresponding to a constant diaphragm aperture value prescribed for flash photography, and
- e. a flash control circuit coupled to said discharge tube to control the amount of light from said flash discharge tube based on data depending upon the distance to an object, and
- B. a camera, including and objective having a diaphragm defining an exposure opening, and automatic means coupled to the diaphragm for setting the diaphragm aperture to the prescribed aperture value in response to the energy accumulation completion signal at a time of flash photography, said automatic means including:
- a. exposure opening control means coupled to said diaphragm to control the exposre opening,
- b. a diaphragm aperture signal forming circuit to form diaphragm aperture signal to control diaphragm aperture,
- c. and exposure control circuit to control the exposure opening control means on the basis of the output of said diaphragm aperture signal forming circuit, and
- C. (a) a selector circuit in one of said flash device and said camera and connected to said exposure control circuit and responsive to the accumulation completion signal for automatically switching the diaphragm aperture signal to the prescribed diaphragm aperture value information signal and transmitting said prescribed diaphragm aperture value information signal to said exposure control circuit, and for controlling the exposure opening control means on the basis of the prescribed diaphragm aperture value information signal.
8 more elements
A camera capable of flash photography using a computer stroboscope containing a charge completion signal forming circuit to form a charge completion signal when a main capacitor is charged to a prescribed level, said camera comprising an objective and a diaphragm as well as a shutter, said camera further comprising;
- a. exposure opening control means coupled to the diaphragm to control the diaphragm exposure opening,
- b. a diaphragm information forming circuit to form diaphragm aperture information signal,
- c. a control circuit coupled to said exposure opening control means and said diaphragm information forming circuit for forming a control signal to control said exposure opening control means, said control circuit being operable in a flash mode to form a control signal corresponding to a prescribed diaphragm aperture valve during flash photography and an ordinary photographic mode to form a control signal corresponding to the output of said diaphragm aperture information forming circuit, and
- d. a selection circuit connected to said control circuit for automatically selecting the flash mode in response to the charging completion signal of said computer stroboscope, for controlling the exposure opening control means with a control signal corresponding to said prescribed diaphragm aperture value.
1 more element
A flash device for use in combination with a camera including a diaphragm control device settable to an ordinary photographic mode and flash mode and controlling the aperture of a diaphragm based on the output of a light sensing circuit, said flash device comprising:
- a. a flash discharge tube,
- b. accumulation means to accumulate flash energy for said flash discharge tube,
- c. accumulation completion signal forming means coupled to said accumulation means to form an accumulation completion signal when the flash energy accumulated at said accumulation means reaches a prescribed level,
- d. flash control circuit coupled to said tube to control the amount of flashing by said flash discharge tube based on the distance to an object, p1 e. informatiom forming means for forming a diaphragm aperture information signal corresponding to a constant diaphragm aperture value prescribed for flash photography,
- f. a signal transmission terminal connected to said accumulation completion signal forming means and transmitting said accumulation completion signal to said diaphragm aperture control device for setting the diaphragm aperture control device to the flash mode, and
- g. a second signal transmission terminal connected to said diaphragm aperture information forming means to transmit the aperture information signal to said diaphragm control device.
3 more elements
A flash camera system, comprising:
- A. a flash light device, having:
- a. a flash discharge tube,
- b. flash energy accumulation means connected to said flash discharge tube to accumulate flash energy,
- c. accumulation completion signal forming means connected to said flash energy accumulation means to form a flashing energy accumulation completion signal when the flash energy accumulated at said flash energy accumulation means reaches a prescribed level, and
- d. prescribed diaphragm information forming means to form a prescribed diaphragm aperture value information signal corresponding to a constant diaphragm aperture value prescribed for flash photography, and
- B. a camera having:
- p2 a. a light sensing circuit to form an output corresponding to an object brightness,
- b. diaphragm control circuit coupled to said light sensing circuit and to said aperture information forming means and having an ordinary photographic mode control circuit to form the diaphragm aperture control signal for controlling diaphragm aperture based on the output of said light sensing circuit and a flash photographing mode control circuit to form diaphragm control signal for controlling the diaphragm aperture based on the output of said prescribed aperture information forming means,
- c. a mode selector means connected to said diaphragm control circuit for setting said flash mode control circuit in an active state in response to said flashing energy accumulation completion for forming a mode control signal to set said ordinary photographing mode control circuit in an inactive state so that the diaphragm is automatically controlled by said flash photographing mode control circuit, and
- d. diaphragm control means coupled to said diaphragm control circuit to control the diaphragm aperture based on the output of said diaphragm control circuit.
7 more elements
A camera for use with a computer stroboscope including accumulation means to accumulate flash energy and accumulation completion signal forming means to form an accumulation completion signal when the flash energy accumulated at said accumulation means reaches a prescribed level, said camera comprising a diaphragm and a shutter, and further comprising
- a. exposure opening control means to control said diaphragm,
- b. a light sensing circuit to form an output corresponding to object brightness,
- c. a diaphragm control circuit coupled to said exposure opening control means, wherein said circuit including an ordinary diaphragm control mode circuit to control said exposure opening control means based on the output of said light sensing circuit and a flash diaphragm control mode circuit to control said exposure opening control means based on a prescribed diaphragm aperture value,
- d. a shutter time control circuit, including an ordinary photographing shutter control mode circuit to control the shutter with a set shutter time and a flash photographing shutter control mode circuit to control the shutter with a shutter time prescribed for flash photography,
- e. a diaphragm mode selection circuit connected to said diaphragm control circuit for selecting the flash diaphragm control mode circuit in response to said accumulation completion signal so as to control the diaphragm with said diaphragm control mode circuit, and
- f. a shutter mode selection circuit connected to said shutter control circuit for selecting the flash shutter control mode circuit in response to said accumulation completion signal so as to control the shutter with said shutter control mode circuit.
3 more elements
Dependencies are inferred from the claim text.