Abstract: In a camera provided with a finder and a photographic lens, the focal length of the photographic lens being variable, there is provided a distance measuring device having a pair of optical elements at the front side of the camera, the optical axes of the pair of optical elements being different from the optical axis of the finder, and a line sensor having a pair of image-receiving areas for receiving a pair of images of a photographed object through the pair of optical elements. The respective image-receiving area of the line sensors are selected depending on the focal length of the photographic lens, which corresponds to the range at which an object to be photographed is located. In addition, there is provided an auxiliary light projector for projecting a pattern image to the object to be photographed, the image magnification of which being variable corresponding to the focal length of the photographic lens.

Abstract: A flash device for a photographing camera comprising an ordinary flash mechanism, an improved flash mechanism including a part of the ordinary flash mechanism, an operation mode controller which selectively switches the operation mode of the flash mechanisms and a control terminal which is provided in addition to terminals electrically connecting the ordinary flash mechanism to the photography camera, the control terminal electrically coupling the operation mode controller to the camera, and with the switching of operation modes of the ordinary flash mechanism and the improved flash mechanism being changed by the operation mode controller in response to an input signal to the control terminal.

Abstract: The power supply in a camera is connected to the camera control section only through a normally-off switch which is rendered conductive only when a switch is operated requesting that as camera control function be performed. The power supply is connected to the function request switches at all times, but only in a high impedance state so that there is substantially no power consumption when the camera is not actually operating.

Abstract: The power supply in a camera is connected to the camera control section only through a normally-off switch which is rendered conductive only when a switch is operated requesting that as camera control function be performed. The power supply is connected to the function request switches at all times, but only in a high impedance state so that there is substantially no power consumption when the camera is not actually operating.

Abstract: The oscillation wave signal generated during lens stop-down is amplified by an adjustable gain amplifier the gain of which is controlled in accordance with the peak value of the oscillation wave signal detected during a predetermined time period, to thereby maintain a substantially constant oscillation wave signal amplitude during lens stop-down.

Abstract: A photoelectric amplifier comprising a photodiode having an anode connected to a gate of a first FET and a cathode connected to a gate of a second FET, with the second FET having a source-gate interconnection so as to be self-biasing. The photodiode cathode is connected to a high impedance feedback loop, including an output transistor, which is connected back to the photodiode anode. In a preferred embodiment, further included is a feedback circuit gain controlling transistor having a base driven by the feedback circuit and a current electrode connected to the source of the first FET.

Abstract: A photoelectric amplifier in a camera exposure system, in which a photodiode is connected across the inputs of an operational amplifier and charges an integrating circuit in a feedback path across the operational amplifier. The resistance of the feedback path can be varied in response to the film sensitivity. The output of the operational amplifier is compared against a films speed reference voltage. Thereby, a reduced range of film speed reference voltages need to be provided because of the optional gain of the photovoltage.

Abstract: A film rewinding device for a camera in which the rewind switch need only be momentarily depressed to initiate the rewinding operation. The rewind switch is a type which remains depressed after momentary activation. Activation of the rewind switch produces a first signal which is ANDed with a second signal which is present when the camera is in a normal state and it is possible to perform a rewinding operation. When both the first and second signals are active, a switching circuit applies power to a control section to effect the rewinding operation. The completion of the rewinding operation is detected by sensing the movement of the film. When the rewinding operation has been completed, the second signal is deactivated, thereby removing power from the control circuitry. The rewind switch is opened when the rear cover is opened.

Abstract: A digitally controlled camera in which a DX code on a film cartridge is read by electrical terminals. Those same terminals are used to output digital data from the camera, such as exposure data or other signals from the digital control means.

Abstract: The aperture value in a camera having a flash unit is controlled by a frequency signal from the flash unit. The frequency of the signal is variable in accordance with the light emission characteristics of the flash unit.

Abstract: A charge detection display type electronic flash in which the fact that the main capacitor is charged is detected and the flash is prevented from operating until the main storage capacitor is fully charged and in which triggering of the flash tube is prevented once the power switch has been turned off. A neon lamp is coupled through a resistor between the output of a DC-DC converter and a parallel combination of an impedance element and a second capacitor. A diode is coupled across the neon lamp. The X contact of the camera is connected between a thyristor which operates the triggering circuit of the flash and the common connection point of the impedance element and the neon lamp. A camera control circuit may be coupled as well to this point.

Abstract: An adaptor for a camera for operating multiple flash units with a single camera device in which all of the flash units simultaneously emit light. Output signals from each of the flash units indicating that the corresponding individual flash unit is ready to emit light are coupled to corresponding inputs of a logical product circuit such as an AND gate. The single output of the AND gate is coupled to a single corresponding input of the camera device. The X contact of the camera device is coupled in common to the actuation terminals of each of the flash units.

Abstract: A gamma switching circuit of a programmed shutter having a voltage conversion circuit which subjects to logarithmic compression an optical current which varies with .gamma.=1 with respect to brightness variation. A constant circuit has only an inflow current available and no outflow current is available at the output terminal thereof. A time setting circuit includes a switching circuit and a shutter controlling magnet driving circuit. The output terminal of the voltage conversion circuit is connected through a series circuit of two resistors to the output terminal of said constant voltage circuit, and the connection point between said two resistors is connected to the input terminal of said time setting circuit. The constant voltage circuit applies a voltage to one input terminal of a differential amplifier circuit, and the collector of a transistor whose base is connected to the output terminal of the differential amplifier circuit is connected to the other input terminal of the differential amplifier.

Abstract: An exposure factor switching circuit in a camera with an exposure control circuit having an emitter follower transistor adapted to apply a voltage through at least one transistor driven by a current flowing in the emitter thereof. A time constant circuit is adapted to control a shutter control magnet with an integration voltage due to a collector current of another transistor to the base of which the output of the emitter follower transistor is applied. A bias current supply circuit is employed having a plurality of transistors one of which is provided with a switch connected to the emitter thereof. The switch is operated to selectively activate the plurality of transistors to vary the emitter current of the emitter follower transistor.