Abstract: A camera system including an electronic flash device with a slave emission function, includes an electronic flash device including: a light-receiving unit for receiving a steep optical signal; a light-emitting unit for slave-emitting illumination light toward an object in response to the optical signal received by the light-receiving unit; a timer for starting a time measurement operation in response to the optical signal input to the light-receiving unit, and permitting an operation of the light-emitting unit after an elapse of a predetermined period of time; an attachment member used for attaching/detaching the device to/from a camera body; and a data communication function unit for exchanging various data including photographing information with the camera body via the attachment member; and a camera body electrically connected to the electronic flash device.

Abstract: A tripod type slave unit comprises a shoe type mount for carrying detachably a mounting leg for strobo device and the like on a portion of a tripod device detachable to an accessory mount of a camera, a control terminal connected to a switching terminal for strobo device and the like carried on the shoe type mount, and a switching circuit connected between both terminals of said control terminal to shortcircuit both the terminals temporarily by means of a photosensor for detecting a leading edge of a flash of a main light source.

Abstract: A photographic system including a flash unit wirelessly controlled. The system comprises a controller interlocked with the photographic camera and a flash unit operable in response to the controller to illuminate object. Start and stop of flashing of the flash unit are controlled by control means in a particularly determined manner so as to prevent maloperation of the unit.

Abstract: An electric flash device for camera of the present invention comprises, substantially, a first flash unit incorporated into a camera, and a second flash unit operated associating with the flash operation of the first flash unit, said second flash unit comprises flash starting means for starting a flash operation of a flash tube by means of receiving a flash light from said first flash unit. The electric flash device of the present invention further comprises means for eliminating or reducing flash light quantity of said flash tube of said second flash unit.

Abstract: A device for activating an electronic slave flash unit for photographic use includes a circuit wherein there is a delay circuit responsive to a light sensing signal after a predetermined time delay to activate a flash unit. The time delay of the delay circuit is adjustable as required, and the delayed operation of the flash of the slave flash unit eliminates incorrect impulse signals being transmitted to light sensors of other slave flash units which would otherwise prematurely extinguish their flash and give a resultant incorrect lighting effect. The power for the circuit is obtained from a capacitor which is energized by a flash unit. The energy in the capacitor is used to power the delay circuit, and a Zener diode and unijunction transistor and variable resistance permit accurate variable time delays.

Abstract: An auxiliary electronic flash apparatus coactuable with a main electronic flash apparatus of the type having a first flash lamp for converting the energy stored on a first main capacitor into light for illuminating a subject, and a control circuit for turning off the first flash lamp when the light emitted from the first flash lamp and reflected back from the subject reaches a predetermined amount. The auxiliary electronic flash apparatus includes a photometric circuit responsive only to the light emitted from the first flash lamp within a predetermined light wavelength range for generating a flash start signal in response to which a second flash lamp in the auxiliary electronic flash apparatus is turned on and for generating a flash and signal in response to which the second flash lamp is turned off.

Abstract: An automatic electronic flash device or computer flash device for cameras. The device includes besides an electronic flash lamp a capacitor capable of being discharged through the flash lamp. Also there is a light sensitive sensor and a device for extinguishing the flash lamp in response to the light falling upon the sensor. There are also provided two signal lamps, one for indicating whether the capacitor is charged, and the other one for indicating that the flash lamp has been discharged. A housing which can be separated from the flash device contains the sensor. The housing is capable of being secured to a camera and both signal lamps are visibly arranged at the rear surface of the sensor housing.

Abstract: Circuits and auxiliary elements for use with a device for controlling the emission of light pulses from a flash unit, which light pulses are produced by the discharge of current pulses from a capacitor, the device including a light sensing element for receiving light produced by the flash unit and reflected from an object in the light path. One such circuit includes a switch which is selectively operable to permit control of termination of the emission of light pulses at either one of two light intensity output levels. Another circuit permits one light sensing element to normally trigger the emission of a light pulse in response to a light pulse from a remote unit, and to be selectively connected to subsequently control termination of such emission. One such element is a special gas filled switching tube having two internal electrodes for triggering conduction through the tube in response to a low voltage.