Abstract: An active rangefinder for use in a camera. The rangefinder has a light-emitting device, a spot light position detector disposed at a given distance from the light-emitting device, head amplifiers, filters having amplification function, synchronous detectors, integrators, an adder, a subtracter, a microcomputer, and an automatic gain control (AGC). The filters are connected to their respective head amplifiers each having an operational amplifier. The gains of the filters are controlled by the AGC according to the output signals from the synchronous detectors.

Abstract: A method of driving the light-emitting devices of a multiple flash rangefinder for use in an autofocus camera in which the rangefinder includes a light-receiving device and an arithmetic processing unit that calculates the distance to the subject from the output signal from the light-receiving device. The light-emitting devices are lit up successively one at a time in such a way that each device emits momentarily and the series of operations is repeated several times.

Abstract: A circuit for detecting back light comprises a time constant circuit including a capacitor selectively connectable in series with either a resistive element, or one of two CdS photoconductive elements used to measure the central and surrounding portions, respectively, of an object being photographed. Three switches separately conect the resistive element and the two photoconductive elements in series with the capacitor. A circuit generates pulses for a length of time governed by a time constant determined by the time constant circuit, and three separate counters store the pulses the number of which is determined by the time constant. An arithmetic circuit processes the pulses stored in the counters to determine the amount of back light present on the object.

Abstract: A range finder for use with a still camera and the like, projects an infrared light beam to an object and the light beam reflected from the object is detected by a split photosensor. The photosensor is made up of two photodiodes connected in opposite polarity relationship so that a differential photocurrent produced by the diode pair is amplified. The reflected light beam is tracked so that the photosensor provides a zero output, and the distance to the object is determined from the time needed to detect the zero photosensor output.

Abstract: A camera shutter has an automatic focusing lens operative when actuated to effect an automatic focusing operation. An actuating ring is normally placed in a non-operating region and momentarily shifted to an operating region during the automatic focusing operation. The actuating ring is sequentially displaceable in forward and reverse direction through the operating region to actuate the automatic focusing lens, and displaceable in the forward and reverse directions in the non-operating region without effecting actuation of the automatic focusing lens. A ratchet mechanism is coupled to the actuating ring for selectively locking and unlocking the actuating ring in the non-operating region in response to the displacement thereof in the forward and reverse directions. A bi-directionally rotatable stepping motor is connected to drive the actuating ring to displace the same in the forward and reverse directions.

Abstract: A flashmatic device for cameras equipped with a programmed electronic shutter having sectors serving also as diaphragm blades, firing the flash at a suitable point in a phase of the shutter operation in which the aperture is gradually opened, to ensure synchronized flash shooting. Even in a case where a sector closing signal is produced earlier than a flash trigger signal, the flash is fired by means of a switch which is closed in relation with the sector closing motion to make flash synchronization possible under any condition.

Abstract: An automatic film sensitivity setting device for cameras in which film sensitivity indicated in coded form on a loaded film package is automatically read in by electric signal terminals and introduced to an exposure control circuit as a parameter for the calculation and control of exposure, characterized in that the device is arranged to elect a predetermined specific film sensitivity in the absence of valid coded information of film sensitivity on a film case of the package, and in the case of an ordinary film package without the coded information, to elect a predetermined specific film sensitivity in the absence of information in any one of the electric signal terminals.

Abstract: An automatic film sensitivity setting device uses part of electrical contacts provided on a film patrone of CAS system to produce from two-bit information a voltage signal indicating the film sensitivity index for the exposure control circuit of a camera. The device includes the circuit for setting the film sensitivity index manually.

Abstract: An active type distance detecting device wherein either a light emitting element or a light receiving element is operated to scan by a scanning means. A signal for driving the scanning means is interposed between pulse signals for causing the light emitting element to emit flickering light so that the former signal may not overlap with the latter pulse signals in order to reduce fluctuations of a load electric current.

Abstract: An electromagnetically actuated shutter for a camera wherein automatic focusing and exposing operation are controlled by means of a single reversible stepping motor.

Abstract: A system for automatically setting the film sensitivity in a camera by reading the film sensitivity in terms of a code through an electric signal terminal attached to a film patrone of the camera and producing an electric signal for automatic exposure control, in which the read code signal is stored at a certain predetermined timing and this stored stable information is used during exposure.

Abstract: Light projected from an active lighting means to an object is reflected by the object, and a light spot is produced on a light-sensitive element by the light reflected from the object. The distance to the object is determined by detecting the position of the light spot on the light-sensitive element.The light-sensitive element for receiving the reflected light from the object has formed on a portion of a surface thereof an insensitive zone which has the same width or the same area as the light image produced by the reflected light and the light-sensitive element moves on an image plane in a certain relationship with the distance to the object whereby a change in a photoelectric output of the light-sensitive element is detected to detect the distance to the object.

Abstract: An active type range finder has a light-emitting element which is pulsatively driven to project light pulses on an object to be photographed. A photodetector element receives the light reflected from the object and produces a photoelectric output signal proportional to the amount of received light. A light-shielding member is scanned over the light-sensitive surface of the photodetector element in correlation with the distance to the object so that the light-shielding member successively shields successive areas of the light-sensitive surface from receiving light. An a.c. amplifier amplifies the photoelectric output signal, and an integrating circuit integrates the amplified photoelectric output signal and produces an integrated d.c. signal having a negative peak value indicative of the position of the scanning light-shielding member which corresponds to the object distance. Detecting circuitry detects the negative peak value and provides a corresponding detection signal indicative of the object distance.

Abstract: A camera shutter utilizes a single photoelectric element in conjunction with a shutter control circuit for controlling the automatic exposure operation of the shutter in dependence on the integrated value of the ambient light received from an object field being photographed, and a flash control circuit for controlling the timing and duration of the flash in dependence on the total integrated value of the ambient light and flashlight received from the object field. The shutter control circuit effects control of the shutter operation before operation of the flash control circuit so that the automatic exposure operation and the flash operation are carried out in series. By such an arrangement, the flash system is operated within the time lag which occurs between the production of a shutter closing signal and the actual start of the shutter closing operation.

Abstract: A distance detector capable of measuring the distance between the range detector and an object by directing a light emitted from a light emission element to the object and receiving the reflected light and advantageously adaptable particularly to small-sized cameras.The light reflected on the object is received by a single light-receiving element. The reflected light is condensed by a condenser and concentrated on the light-receiving element. The light-receiving element comprises an element, for example a photopotentiometric element, varying in the electric output according to the position of the light spot of the reflected light. The output of the element in the form of electric signal continuously varies in proportion to the distance between the range detector and the object.

Abstract: An exposure control circuit for cameras equipped with a self-timer comprises an RC integrating circuit including a capacitor and a resistance for determining an automatic shutter releasing period and a time constant setting circuit employing the same capacitor for switching from the self-timer operating mode to the exposure time control mode. Exposure time is determined by the capacitor and the output signal of a photoelectric conversion circuit. This circuit construction allows a single electromagnet to control both an automatic shutter releasing period and exposure, and a single capacitor to function in three time constant setting operations.

Abstract: An automatic focusing device controls the setting of an actuating member to effect automatic focusing of a camera lens and is used in conjunction with a focus detecting unit which produces a focus detection signal corresponding to the object distance by photoelectrically comparing optical images transmitted by stationary and movable mirror systems. The automatic focusing device comprises pulse generating circuitry for generating pulses at a fixed repetition rate, a first counting circuit for counting pulses such that the number of pulses counted is a function of the angle of displacement of a movable mirror of the movable mirror system during a range scanning operation, and a second counting circuit connected to receive and memorize the pulse count counted by the first counting circuit when a focus detection signal is produced by the focus detecting unit and operative to count pulses such that the number of pulses counted is a function of the extent of movement of the actuating member.

Abstract: In an electric shutter having a photoelectric element, a time constant circuit for use in controlling exposure and a low brightness sensor circuit for use in connecting said photoelectric element in series with a comparator resistance and in sensing a low brightness in reference to its partial voltage, an exposure information input circuit for setting one reference voltage to be applied for determining said trigger levels of the two sensor circuits so as to feed exposure information such as film sensitivity, etc. and further having a function correction circuit between said reference voltage and one of said two sensor circuits.

Abstract: Automatic focusing adjustor device provided with a focusing sensor signal corresponding to an object distance by photoelectrically comparing an optical image obtainable through a fixed mirror and another optical image obtainable through a movable mirror wherein when the focusing sensor signal is not obtained, two steps of distance adjustment may be made by an output signal from a brightness sensor circuit for use in sensing a brightness of the object.

Abstract: In a program shutter of the type in which the aperture opening gradually increases with the lapse of time, informations such as sensitivity of the film and the object distance are introduced by an electric circuit.The system has a switching circuit for exposure control. The trigger level of the switching circuit is determined in proportion to the film sensitivity and the object distance to vary the exposure control time corresponding to the informations to automatically determine a proper aperture for flash photography.The system is capable of providing a warning indication prior to the shutter operation if the exposure control time thus obtained is longer than the time during which the aperture is fully opened.