Olympus Optical Company, Ltd.

Isao Kondo

Yukio Nakajima

Yoshihisa Maitani

Akihiko Hashimoto

Osamu Kawarada

Kunio Shimoyama

Soichiro Matsuzaki

Tamotsu Koiwai

Katsuhiko Tsunefuji

Masahiro Kitagawa

Kazuyuki Nemoto

Hiroaki Nakamura

Takeshi Nakane

Toyohiko Kimura

A power supply unit for electronic flash includes a plurality of charging units connected to a main capacitor of an electronic flash through diodes which prevent a reverse current flow. Each charging unit includes a d.c. source and a booster converter. An efficient utilization of the source battery is attained by reducing loading upon each source. The use of components of reduced capacity enables a reduction in the size of the overall unit. A single power switch enables a simultaneous initiation of the charging of the main capacitor by all of the charging units. When the main capacitor is charged to a given value, disable means are simultaneously operated in response to an output from charging voltage detecting means, thus simultaneously ceasing the charging operation of the charging units.

Power supply unit for electronic flash

A camera with an electrical shutter comprises auxiliary shutter closing means which is responsive to an electrical signal supplied from an electronic flash to operate a photometric circuit of the camera in a normal manner. During a flash photographing operation using an electronic flash, if an amount of light incident on a light receiving element in the photometric circuit is less than a given value, an electrical signal which is supplied by the electronic flash upon occurrence of the flashlight illumination from a flash discharge tube is applied to the auxiliary closing means, thereby forcibly closing the shutter.

Camera with electrical shutter

An illumination mode switching circuit for an automatic electronic flash includes an illumination mode selecting, changeover switch having a first terminal which is utilized to establish an automatic illumination control level, a second terminal which provides a manual illumination control, and a third terminal which enables a full emission of flashlight from a flash discharge tube. An isolation diode is connected between the second and the third terminal. In this manner, any one of the three modes can be selected by operating the changeover switch.

Illumination mode switching circuit for automatic electronic flash

A photometry power supply for automatic electronic flash comprises an impedance element through which part of the charge stored across a main capacitor of the electronic flash discharges to develop a voltage thereacross which may be used as a power supply for a photometric circuit.

Photometry power supply for automatic electronic flash

An electronic flash assembly including a plurality of flash units for illuminating an object, one of which determines reflected light from the object being photographed and also produces a flashlight interrupting, control signal when a proper amount of illumination has been given. The control signal is supplied to all the flash units through an external control terminal, to interrupt the emission of flashlight from the plurality of flash units.

Multiple electronic flash controlling apparatus

A camera and electronic flash combination is provided which permits the electrical circuits of a camera and an electronic flash to be coupled to each other through four terminals, thus achieving an efficient transfer of signal between both units. The electronic flash includes an illumination control circuit which can be controlled by an illumination control signal from the camera, preferentially from an output from a photometric circuit contained in the electronic flash, by an operation of a changeover switch which is disposed within the camera.

Camera and electronic flash combination

An automatic-light control electronic flash device used in automatic exposure camera having a gate circuit connected between an electromagnetic device for driving a shutter rear curtain and a light control signal output terminal. The gate circuit is enabled by a flash ready signal produced from the automatic-light control electronic flash device thereby to permit a light control signal producing in response to the deenergization of the electromagnetic device to pass therethrough to the automatic-light control electronic flash device.

Automatic-light control electronic flash device for use in automatic

A camera includes a circuit which determines the level of a supply voltage and a self-timer delay circuit associated with an electrical shutter. The camera also includes an acoustic indicator which includes a pulse oscillator and a small size acoustic alarm unit and which operates to produce a sound substantially continuously to indicate the level of the supply voltage and to produce a sound intermittently in order to indicate that the self-timer is in operation.

Camera having an acoustic indicator for generating sounds to indicate

A single-lens reflex camera comprises a gear rotated when a shutter button is depressed, a movable mirror rotated upward to the prescribed position, a stop-driving mechanism, and a control mechanism which transmits the rotation moment of the gear to the movable mirror and stop-driving mechanism to lift the movable mirror so that after the movable mirror is lifted, it actuates the stop-driving mechanism in the stop-down mode.

Single-lens reflex camera

In an electrically-controlled shutter circuit for use in automatic exposure camera, a gate circuit is connected between an electromagnetic device for driving a shutter rear curtain and a light control signal output terminal. The gate circuit is enabled by a flash ready signal produced from an automatic electronic flash device connected to the automatic exposure camera thereby to permit a light control signal producing in response to the deenergization of the electromagnetic device to pass therethrough to the automatic electronic flash device.

Electrically-controlled shutter for automatic exposure camera

A power supply circuit for strobo unit includes a DC-DC converter which steps up a low voltage from a d.c. source to a higher voltage. The converter comprises an oscillation transformer, a PNP transistor and an NPN transistor, both of which are used to form an oscillation circuit. The circuit arrangement provides a stabilized oscillation and eliminates the likelihood of producing an electric shock.

Power supply circuit for strobo unit

A signal system includes a switching element which is turned on or off in response to an electrical signal. The signal system includes a field effect transistor which is arranged such that the drain current does not change in response to a variation in voltage across the source and the drain of the transistor, whereby every signal is applied to the switching element when a circuit voltage is applied to the switching element while a signal is prevented from being applied to the switching element when a circuit voltage is not applied to the switching element.

Signal system

An electrical shutter comprises a first detent member which maintains a shutter drive member at its start position, and a second detent member which maintains a shutter in its open position. Upon abutment of the shutter drive member, both the first and second detent members are urged to move in a direction away from the drive member in response to the rotating force of the shutter drive member. The shutter also includes electrical circuits for accessory features which are connected through normally open switches with the common bus of the power source.

Electrical shutter for camera

An adaptor for an auto strobo unit comprises a trigger signal feed circuit for supplying a trigger signal to a flashlight trigger circuit of said auto strobo unit in response to the closure of a synchro contact of an automatic exposure controlled camera, a polarity inverter for inverting the polarity of an illumination interrupt signal supplied by a photometric control circuit of the camera to a polarity which is suitable to activate an illumination interrupt circuit of the auto strobo unit, an amplifier for amplifying an illumination interrupt signal to a given level, and circuit means for feeding the polarity inverter or the amplifier when the trigger signal feed circuit is operated. The adaptor enables an automatic exposure controlled camera to be combined with any kind of an auto strobo unit.

Adaptor for auto strobo unit

A flashlight apparatus includes a power switch, formed by a changeover switch, which is connected in a path to discharge a primary discharge capacitor and a trigger capacitor in its off condition to disable a flashlight operation. Simultaneously, a neon tube light which indicates the completion of charging of the primary discharge capacitor is turned off, indicating the off position of the power switch.

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Hachioji, Japan

Isao Kondo