Seiko Koki Kabushiki Kaisha

Takeo Saito

Youichi Seki

Kiyoshi Kitai

Shinji Nagaoka

Takashi Segawa

Yuzuru Takazawa

Yoichi Seki

Hiroaki Ishida

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.

Automatic film sensitivity setting device for cameras

A device for detecting coincident focusing points for use in the controlling of the focusing of an automatically focusable lens comprises a single array of light receiving transducers for converting the distribution of light intensity of an image applied thereon to a set of corresponding electrical signals. The image applied to the array is from a first optical path from an object through the lens and from a second optical path from the object. At least one shutter is provided for cutting off one of the optical paths to alternatively effect the application of light from the one optical path on to the array to produce a first set of signals and thereafter the light from either the other optical path or the sum of the two optical paths on to the array to produce a second set of signals. The first set of signals are processed to produce a third set of signals which correspond to the ratio of each signal therein with respect to another of the signals and the second set of signals is processed to obtain a fourth set of signals corresponding to the ratio of each signal with respect to another of the signals. The third and fourth sets of signals, for each transducer, are compared and a signal is produced when a favorable comparison is obtained.

Device for detecting coincident focusing points

An illuminating system is provided for a focus detecting device capable of producing range detection signals corresponding to the distance between the camera and the objects by receiving with a plurality of photoelectric elements the light of the objects transmitted through a fixed light passage and a movable light passage provided with a movable mirror. The illuminating light source of the illuminating system is disposed to project the illuminating light through the movable light passage. When the brightness of the objects is low, the plurality of photoelectric elements are integrated into practically a single photoelectric element to combine the outputs of respective photoelectric elements into a single output thus receiving the reflected light of the illumination and providing a focus detection signal.

Focusing detecting device

A step second timepiece comprises a quartz crystal oscillator and a frequency divider containing a reset circuit. The reset circuit includes a reset switch operable such that the time interval from when the reset switch is released up to when the next pulse is fed from the frequency divider is shorter than the pulse interval of the successive pulses fed from the said frequency divider thereby compensating for time lag associated with the release of the reset switch.

Timepiece circuit for compensating time lag joined with reset releasing

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. A detector detects when the pulse count counted by the second counting circuit reaches a predetermined count and produces a corresponding output signal which is used to terminate the movement of the actuating member to thereby effect focusing of the camera lens.

Automatic focusing device

A focal point detecting device comprises a light-receiving device having a plurality of light-receiving elements which receive incident light coming from two different light paths. In the first step, the light-receiving device receives the incident light coming from the second light path while the first light path is blocked and the values of the photoelectric outputs A.sub.1, . . . A.sub.n of each of the light-receiving elements are compared one with another and the compared values stored in a memory circuit. In the second step, the light-receiving device receives either the incident light coming from the first light path while the second light path is blocked or the incident light coming from both the first and second light path and the values of the photoelectric outputs B.sub.1, . . . B.sub.n of each of the light-receiving element are compared on with another and the compared values are compared with the contents stored in the memory circuit and a focal point coincident signal is fed out in response to a favorable comparison.

Focal point coincidence sensing device

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.

Automatic focusing adjustor device

A camera shutter digital control circuit having a counter for counting a number of pulses representative of exposure time and for reading-out the counted pulses to control exposure time. An adjustable delay circuit synchronizes shutter opening and the initiation of memory read-out. Upon the initiation of shutter opening a signal is applied to the delay circuit, which is adjusted to develop a delay equal to a particular shutter opening time. The delayed signal is then applied to initiate reading-out of the control pulses so that the exposure time is controlled in synchronism with the shutter opening.

Digital camera shutter control circuit having memory read-out/shutter

A light emitting indicating circuit comprises a first and second inverter circuit which are each comprised of a pair of complementary transistors connected in series. A motor driving coil and a capacitor are connected in series between respective outputs of the inverter circuits, and the inverter circuits are effective for applying repetitive complementary electrical driving signals for repetitively flowing a current in alternating directions through the series combination of motor driving coil and capacitor to repetitively energize the motor driving coil. An indicating circuit responsive to the electrical driving signals indicates energization of the motor driving coil. The indicating circuit is comprised of a light emitting diode connected in parallel with the motor driving coil for emitting light to indicate energization of the motor driving coil.

Light emitting indicating circuit for a timepiece

An electric shutter circuit having an exposure time display disabled in synchronism with the opening of a camera shutter. A brightness-time conversion circuit and a pulse generator together develops a plurality of pulses the number of which is representative of the exposure time and which are stored in a reversible counter. Upon actuation of a shutter release mechanism a display circuit is enabled to display the exposure time by displaying a visual signal determined by the number of pulses stored in the reversible counter. The display circuit is disabled in synchronism with the shutter opening. In one embodiment a Schmidt trigger circuit is triggered by the shutter release mechanism to disable the display circuit.

Shutter control circuit having exposure time display

In a programming electric shutter for a camera, the photoconductive element receiving light from the subject to be photographed comprises a plurality of photoelectric bodies. An exposure multiple setting device permits using one or more of the photoelectric bodies selectively according to the exposure factors or the sensitivity of the film to be used.

Exposure multiple setting device for programming electric shutter

An exposure time control device of an electric camera shutter includes a brightness time conversion circuit for developing a single pulse having a width representative of the brightness of a subject to be photographed and a reference pulse generating circuit for generating reference pulses at a standard rate. A reversible counter counts the reference pulses for a period of time equal to the duration of the single pulse. Upon termination of the single pulse, a reversible counter control circuit applies control signals to the reversible counter to read-out the count stored therein for controlling the shutter exposure time. A selector switch selects the input position of the reference pulses to the reversible counter in dependence upon exposure time factors other than brightness of the subject thereby enabling the selection of the exposure time in accordance with the subject brightness as well as other factors, such as film sensitivity and diaphragm setting.

Exposure time control device for electric camera shutter

An exposure time control device of an electric shutter includes a brightness-time conversion circuit for developing a single pulse having a width representative of the brightness of a scene to be photographed and a standard pulse generating circuit for generating pulses at a standard rate. A reversible counter counts the standard pulses for a period of time equal to the duration of the single pulse. Upon termination of the single pulse, a reversible counter control circuit applies control signals to the reversible counter to read-out the count stored therein for controlling the shutter exposure time. A delay circuit develops a trigger pulse upon opening of the shutter. The trigger pulse is applied to the reversible counter control circuit, and if it is applied prior to the termination of the single pulse, read-out of the count stored in the reversible counter is initiated prior to termination of the single pulse.

Exposure time control device of electric shutter for camera

An electric camera shutter of the type having a digital recording and reproducing system has a self-timer mode and has a counter circuit for counting and memorizing pulses produced by a pulse generator. In one mode of operation, the exposure time is controlled in accordance with the memorized content of the counter circuit and when in the self-timer mode, the output of the counter circuit controls the energization of a self-timer operation indicator circuit which indicates operation in the self-timer mode.

System for indicating the operation of a self-timer in an electric

A shutter control circuit including a brightness-time conversion circuit for developing an output pulse having a duration representative of exposure time, and a standard pulse generating circuit for generating standard pulses at a certain rate. A reversible counter operable in an addition mode and a subtraction mode counts the standard pulses for the duration of the output pulse of the brightness-time conversion circuit so that the number of counted pulses is representative of exposure time. The reversible counter is then operated in a subtraction mode to read-out the counted pulses to control exposure time. The shutter control circuit further includes circuitry for operating the counter in the addition mode and for applying a selectable number of standard pulses to the reversible counter in order to determine exposure time. When the brightness-time conversion circuit controls the number of standard pulses counted, the control circuit is operative in an automatic mode, and when the number of standard pulses counted are manually selected the control circuit is operative in a manual mode. The shutter control circuit also includes circuitry for reducing the duration of the output pulse of the brightness-time conversion circuit substantially to zero so that the brightness-time conversion circuit is rendered ineffective to determine the exposure time when the shutter control circuit is operated in the manual mode.

Growing community of inventors

Yotsukaido, Japan

Takeo Saito