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: An exposure indicating device for use in a photographic camera which includes a light measuring circuit for generating an output representative of scene brightness, a reference voltage circuit for producing reference voltage, a first switching circuit and a second switching circuit receiving the outputs of the light measuring and reference voltage circuits, and indicating means responsive to outputs of the first and second switching circuits. The indicating device indicates that automatically controlled exposure factor, i.e., shutter speed or diaphragm aperture, will be higher or lower with respect to more than one standards, without any change-over of switches. For example, this device indicates that shutter speed to be effected automatically will be in any of blur occurring range, available range and upper outside range.

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: A focus detecting photoelectric device herein disclosed is usable in a focus control system and is placed on an image plane where an optical image of a subject to be, for example, photographed through an objective lens assembly is focused to detect whether the image has been exactly focused or whether the image is out of focus. An output signal from the photoelectric device herein disclosed is used to control the focus control system to effect the desired focus control in relation to the objective lens assembly. To this end, the focus detecting photoelectric device is composed of at least one group of photoelectric elements, such as photodiodes, connected in series to each other with the cathode of one photoelectric element connected to the anode of the other photoelectric element. These photoelectric elements of the group may be formed on a semiconductor substrate in a predetermined pattern by the use of a known IC circuit making technique.

Abstract: A control device for controlling the exposure time automatically for an electric shutter, in a single reflex camera of the so-called "through the lens" photometric type which determines the brightness of an object by means of the light past through the projection lens of a camera.

Abstract: In an exposure meter having a row of lighting elements, such as lamps or light-emitting diodes, which correspond to respective exposure values, an improvement is made in that by utilizing a capacitor-charging integrating circuit, a constant current circuit and a ring-counter, an exposure value between two neighboring steps of the above-mentioned exposure values can be indicated by lighting said two lighting elements, and in that ranges of exposure indication can be switched by shifting a dial plate, which is facing the lighting elements, in interlocking relation with a range-shifting switch for switching its circuit for range selection, thus enabling a doubling of the steps of exposure values to be indicated with a limited number of lighting elements.

Abstract: Light responsive circuit of low current consumption and low cost and used for camera exposure control and/or exposure indication. The circuit includes a field effect transistor, a photodiode connected between gate and source of the field effect transistor, a transistor having a collector connected to the gate of the field effect transistor and further having a base connected to the source of the field effect transistor, and a control circuit for controlling base voltage of the transistor to regulate source potential of the field effect transistor.

Abstract: An automatic focus control device has an optical system including an image scanner. The image scanner is disposed between a range-finding lens and at least one light receptor element and on the path of travel of the incoming light towards the light receptor element through the range-finding lens. A mechanism is also disclosed for simultaneously measuring the object-to-lens distance and detecting the contrast of an image of the object projected on the scanner merely by moving the scanner in a direction diverging from the optical axis while a parallel relation between the plane of the scanner and the plane perpendicular to the optical axis is retained.

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 photoelectric focus detecting member includes a semiconductor substrate of a first polarity and at least two closely transversely spaced parallel longitudinally extending photosensitive laminae of a polarity opposite to the first polarity to form corresponding photodiodes. Each of the photosensitive laminae is masked to provide regularly spaced light receiving areas alternating with masked areas, the light receiving areas of successive transversely spaced photodiodes being relatively longitudinally offset to present a checkered pattern. The detecting element is positioned in the focal plane of a lens and is either stationary or oscillated. The difference in potential between the diodes or the amplitude of the AC current in a circuit including the photodiodes is a function of the condition of focus of the lens.

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.

Abstract: A light measuring circuit for an exposure time control device uses a photodiode to measure the object brightness and a logarithmic compressing diode to provide negative feedback between the output terminal and one input terminal of a differential amplifying circuit. The output of the light measuring circuit is summed with signals representing film sensitivity and diaphragm aperture setting and the resulting exposure time control signal is compensated for changes in temperature. An antilogarithmic converting circuit generates a signal proportional to the logarithmic value of the compensated exposure time control signal. The antilogarithmic converting circuit operates at the same reference potential as the differential amplifying circuit and its output is integrated and then used to terminate exposure.

Abstract: A control device for controlling the exposure time automatically for an electric shutter, in a single reflex camera of the so-called "through the lens" photometric type which determines the brightness of an object by means of the light past through the projection lens of a camera.

Abstract: First and second output voltages are generated respectively in accordance with the logarithm of the intensity of light and as a function of a manually set exposure condition. A control signal to initiate shutter closing is generated when a signal which changes in proportion to the logarithm of an elapsed time period initiated by shutter release operation plus the second output voltage is substantially equal to the first output voltage. The control device includes a circuit for comparing the voltages. The device may be modified to generate a third output voltage which changes in response to the change of the signal and then comparing the first output voltage with the second plus the third output voltage.