Abstract: An automatic exposure control system for a single lens reflex camera, of the type wherein diaphragm blades defining a diaphragm aperture are driven in response to a camera release operation to change the aperture in accordance with the light from an object to be photographed (object light) as measured by a light measuring device which has a photoelectric element adapted to receive the object light through changing diaphragm aperture as well as through the camera objective. When the output of the light measuring device reaches or goes beyond a given level, a control device generates an output signal to actuate a first electromagnetic device which stops the operation of the diaphragm blades so that a diaphragm aperture suitable for the object brightness is determined as a function of a set shutter speed and a set film sensitivity.

Abstract: A lamp control circuit for energizing a data imprinting lamp in response to an actuation of a flash trigger switch in a camera, for a given period so that data images illuminated by the lamp are imprinted on a film with a suitable exposure. The control circuit includes a series connection of a SCR element and a capacitor, a trigger circuit for applying a single pulse to the control terminal of the SCR element, a capacitor discharge circuit for discharging with a given time constant the capacitor that has been charged through the SCR element, and a switching circuit for energizing the lamp while the terminal voltage of the capacitor is above a threshold level. The trigger circuit has a high input impedance to protect the control circuit from high voltage which otherwise may be applied thereto through a camera synchro terminal to which the input terminal of the trigger circuit is connectable.

Abstract: An automatic focus control camera which includes automatic exposure control means, automatic focus adjusting means, and flash means. These three means are arranged to have a power source in common, and furthermore, the automatic focus adjusting means and flash means are supplied with electric power through an electric voltage boosting circuit which is arranged not to function during an exposure period for taking photographs. Moreover, an electric voltage checking circuit is included for checking a voltage supplied to the automatic focus adjusting means so that the shutter can not be released unless the voltage reaches a predetermined level.

Abstract: In a photographic camera having programmed automatic exposure control, a light measuring output is produced by measuring scene light and an exposure value signal is generated in response to the light measuring output. A time value and aperture value signal are automatically varied as a function of the changes in the exposure value signal, which function is adapted to be altered in a predetermined manner by the change in the exposure value signal. The aperture size is determined in response to the size in the aperture value signal and the exposure time is determined in accordance with the time value signal.

Abstract: An auto-focus camera including an automatic rangefinder device for generating a distance signal indicative of the distance between the camera and a target object to be photographed, a timer circuit for generating an output signal a predetermined time after a power switch is closed, to place a lens drive mechanism in an operative condition for repositioning an objective lens assembly of the camera in search of the true focus setting, and a lens arresting circuit including electromagnetic units. Either of the electromagnetic units is operable to arrest the objective lens assembly at a corresponding focal position when energized by the distance signal. The automatic rangefinder device can measure the distance from the camera to the target object independent of the release of the lens drive mechanism.

Abstract: A position-to-digital encoder for generating digital signals in the form of binary code in accordance with the relative positions between a pair of brush contacts and a series of contacts arranged in order. The latter contacts are disposed in a row along the path of movement of the brush contacts, with equal pitches and gaps between adjacent contacts. The brush contacts are spaced from each other along their path of movement with such a distance that two brush contacts are in contact with a single one of the series of contacts or with an adjacent two of the series of contacts, respectively. One line extends from each contact to a decoder which generates signals in accordance with which contact or contacts of the contact series is engaged by the brush contacts.

Abstract: An exposure meter for use in photography which includes means for measuring brightness at a plurality of places in a scene to be measured for exposure, means for calculating frequency distribution of the brightness which divides brightness value into many stages and counts frequency of occurrence of brightness at each of the stages, and means for calculating, under designated conditions, position whereat film latitude is to be present within the width of the brightness distribution.

Abstract: An exposure meter provides a display indicating the brightness of selected portions of a scene to be photographed. In one embodiment, a photometering block including a plurality of light sensitive elements is employed, and there is an automatic fixed display indicating the brightness level of the brightest and the darkest portions of the objective scene together with a display of a median value. Another embodiment employs a spot photometering device with only one light sensitive element, and a display of the brightness level of different portions of the scene selected by the photographer.

Abstract: In a photographic camera capable of programmed automatic exposure control, circuitry is provided for also enabling exposure time-preferred automatic diaphragm control and diaphragm-preferred automatic exposure time control. The diaphragm is settable to an initial aperture size, which may be the fully opened aperture, and is capable of being changed to different aperture sizes. A first signal is generated in accordance with the logarithm of the light intensity measured through the diaphragm. A second signal is generated in accordance with a manual exposure time setting circuit. A third signal intermediate the first and second signals is generated with a predetermined ratio between the difference of the first and third signals with respect to the difference between the third and second signals.

Abstract: Dating information is applied to camera film from date information displaying circuitry which receives decoded electronic time signals generated by a chronometer. A first power source energizes the chronometer and a second power source energizes the decoder and display circuitry and other components such as the exposure control circuit. A monitor is provided to enable the camera operator to observe the date information. Manually operable switches are provided to independently actuate the dating apparatus and the exposure control circuit as well as to independently operate the display circuitry and the monitor.In a modified embodiment, logic and switching circuitry are provided to monitor and date either exposure data obtained from a light measuring circuit and analog/digital converter or the date information generated by the chronometer. A manually independently operable switch for actuating the display circuitry is ganged with the switching circuit to expose the date information on the film.

Abstract: Information setting apparatus for a camera comprises pulse generating circuitry, pulse counting circuitry and apparatus for visually displaying variable digital information represented by the pulse count in the pulse counting circuitry. The digital information displayed is changed by altering the pulse count stored in the counting circuitry. A manually operable switch stops the pulse input to the counting circuitry to fix the digital information displayed by the display apparatus in accordance with the desired setting. Apparatus is provided for projecting an image of the displayed information onto the camera film. In cameras provided with a viewfinder, the image of the displayed information is projected into the viewfinder field of view.

Abstract: A camera having an electrically controlled exposure is capable of mounting thereon or incorporating therein an electronic flash device which includes a flash tube, a main capacitor for firing the flash tube and a trigger circuit having a trigger capacitor. To initiate the flashing of the flash tube, the trigger capacitor, which has been charged to a voltage level corresponding to that across the main capacitor, is discharged in synchronism with the opening of a shutter through a firing circuit which is made conductive only when the brightness of an object is lower than a predetermined level. A first transistor is made conductive upon the opening of the shutter only when the brightness of the object is lower than the predetermined level and a second transistor is connected in series with the first transistor and made conductive only when the trigger capacitor is charged up to a sufficient level.

Abstract: Light measuring circuit for camera automatic exposure control measures scene light passing through the objective and reflected at the film surface and/or the shutter curtain surface located at the exposre aperture of the camera. The measuring circuit is provided with a compensating circuit for compensating the light responsive output for the difference of light reflecting power of the surfaces of the film and the shutter curtain. The compensating circuit is actuated in a predetermined timing relationship with the travel of a shutter curtain.

Abstract: An exposure control device for a photographic camera uses a conventional exchangeable lens and achieves a highly accurate exposure control commensurate with a pre-selected shutter speed by a light measuring device measuring scene light transmitted through the objective lens, diaphragm, and exchangeable lens. The device also permits exposure control commensurate with a pre-adjusted diaphragm aperture by storing the output from the light measuring device determined with the adjusted diaphragm aperture to control the shutter speed.

Abstract: In an automatic control apparatus for controlling the quantity of light from a flash device, a first photocell device, responsive to the light from the flash device, is serially connected with a second photocell device, responsive to light reflected from the photographic object, and the output from the second photocell device is integrated and used for energizing known apparatus for preventing the light generated by the flash device from reaching the photographic object to optimize the light illuminating the photographic object. The second photocell device has a lower output than the first photocell device, thereby enabling the output from the second photocell device to determine the light measurement. The first photocell functions as a gate in response to the direct light emission from the flash device to prevent spurious and undesirable actuation of the second photocell device.The first and second photocell devices may each be phototransistors or photodiodes.

Abstract: An automatic exposure time control circuit for use with a camera having a shutter. A light measuring circuit for measuring the scene brightness passing through the camera lens produces an electric signal proportional to the logarithm of the scene brightness. An A-D converter circuit converts the output signal from the light measuring circuit to a digital signal. A first decoder, having a plurality of output terminals, receives the converted, digital signal and produces an output at a corresponding one of the output terminals. An exposure time control circuit, comprising a binary counter having the same number of stages and output terminals as the number of output terminals of the first decoder is set to the output of the decoder upon release of the shutter.

Abstract: An automatic focusing apparatus for use in a photographic or television camera having a lens system movable in predetermined incremental displacements in relation to a subject to be photographed in search of the true focus setting. A scanner is provided for scanning the image of the subject and for generating a serial video signal indicative of the image of the subject. This serial video signal is processed by maximum and minimum value detectors which generate signals indicative of the maximum and minimum values of the serial video signal to an extreme value detector through a difference detector. Output from the extreme value detector indicates that the image of the subject is focused in the image plane.

Abstract: An exposure control device for a photographic camera uses a conventional exchangeable lens and achieves a highly accurate exposure control commensurate with a pre-selected shutter speed by a light measuring device measuring scene light transmitted through the objective lens, diaphragm, and exchangeable lens. The device also permits exposure control commensurate with a pre-adjusted diaphragm aperture by storing the output from the light measuring device determined with the adjusted diaphragm aperture to control the shutter speed.

Abstract: In an exposure control device for a photographic camera a shutter speed control signal generating circuit measures scene light transmitted through an objective lens and a diaphragm for automatically controlling the shutter speed commensurate to the measured light output. A control output signal is generated in response to a manually selectable shutter speed. A diaphragm control device controls the diaphragm aperture according to the difference in the light measuring output and shutter speed output signal. The light measuring and shutter speed output signals are selectively connectable to a shutter speed control device for exposure control. A portion of the automatic shutter speed control signal is added to the manually selected shutter speed control signal so that diaphragm aperture control is effected according to the difference between the combined signal and the automatic shutter speed control signal.

Abstract: A mechanism for determining the focus by an objective lens of an image on a focal plane includes a needle shaped or other narrow scanning mask transversely oscillated in the focal plane between the lens and a transversely extending photoelectric element exposed to the mask intercepted image. The output of the photosensitive element is coupled by way of a high pass filter or differentiating circuit and a rectifier to a meter, the maximum meter reading indicating maximum AC output and hence maximum focus. The output of the photosensitive element is also connected through a low-pass filter to a meter or exposed control mechanism.