Olympus Optical Company, Ltd.

Masahiro Kitagawa

Yoshihisa Maitani

Akihiko Hashimoto

Kunio Shimoyama

Muneaki Yoshida

Kazunori Mizokami

Isao Kondo

Kazuyuki Nemoto

Michiharu Saito

A motor drive which is adapted to be used with a camera having a mechanical shutter release mechanism is modified to enable the motor drive to be mounted in a camera having an electromagnetic shutter release mechanism, by providing a circuit which produces an electromagnetic release signal. The likelihood of blurring which may be caused by the rotation of a motor during the exposure of a film and which may be caused by the mere provision of the circuit for producing an electromagnetic release signal is avoided by preventing the rotation of the motor during the exposure of the film. In addition, difficulties are also avoided which are experienced when a film, not subject to any winding operation, is loaded into the camera.

Motor drive for camera

An automatic exposure control circuit for camera having the capability to control the amount of light emitted by a flash discharge tube of an electronic flash comprises bias current booster means which becomes operative as the flash discharge tubes begins to emit light, thereby increasing the speed of response of the control circuit without increasing an input current thereto.

Automatic exposure control circuit for camera

Apparatus for automatically synchronizing a camera with an electronic flash is provided in accordance with the teachings of the present invention. The inventive apparatus determines if a photographing mode employing an electronic flash has been established by detecting whether or not a power source of the electronic flash is enabled. Upon a detection of a photographing mode employing an electronic flash, an exposure period synchronized with the operation of the electronic flash is automatically established. However, when no electronic flash is to be utilized, an exposure period appropriate to an automatic photographing mode is established.

Camera automatically synchronized with an electronic flash

An apparatus for determining the amount of light reflected from a focal plane shutter includes a photoelectric transducer element which determines light reflection from the shutter blind surface and the film surface. The transducer element produces a photocurrent which charges an integrating capacitor. A correcting capacitor is disposed so as to be connected in parallel with the integrating capacitor during a part of the exposure time in order to correct the output voltage thereof for different reflectivities of the film surface and the shutter blind surface. The correcting capacitor is charged to the same voltage as that appearing across the integrating capacitor at the time the correcting capacitor is connected in parallel with the integrating capacitor.

Apparatus for determining light reflection from a focal plane shutter

A camera with operation indicator for auto-strobo unit which includes a light emitting element which indicates the completion of a flashlight illumination by the strobo unit. The operation indicator includes a separate light emitting element located within the finder of the camera to provide a luminous indication within the finder whether a flashlight illumination from the strobo unit has been properly given.

Camera with operation indicator for auto-strobo unit

An information display device for a camera which comprises a power source, an information display circuit, a timer circuit, and switch means for operating the timer circuit to connect the information display circuit to the power source for a fixed time. The switch means includes a first switch which is turned on while being shifted from an OFF to ON position, a second switch connected in series with the first switch, and a third switch connected in parallel with the second switch and interlocking with the first switch. The third switch is so designed as to be turned on to operate the timer circuit while the first switch is shifted from the OFF to ON position and to be already turned OFF when the first switch is brought to the ON position. Preferably, the first and third switches are rotary switches with a common movable contact, and the second switch is a self-restoring switch, such as a push switch.

Information display device for camera

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 photometric apparatus for single lens reflex camera and of the type in which an exposure value is determined by photometry of light which is transmitted through a photographic optical system and is reflected by at least one of the surfaces of a shutter blind and a film, said apparatus comprising a photoelectric transducer element for receiving light reflected by at least one of the surfaces of a shutter blind and a film, and an operational amplifier for biasing the photoelectric transducer element to maintain the voltage applied thereacross substantially null, thereby enabling a photometric output of the photoelectric transducer element to be effectively derived even when the amount of light received is minimal. A second photoelectric transducer element is provided for receiving reflected light from the reflecting mirror that is adapted to be switched between the viewfinder light path and the photographic light path and display means for displaying the operation of the shutter dependent upon the light which is incident upon the aforesaid second transducer element.

Photometric apparatus for single lens reflex camera

A photometric apparatus for single lens reflex camera and of the type in which an exposure value is determined by photometry of light which is transmitted through a photographic optical system and is reflected by at least one of the surfaces of a shutter blind and a film, said apparatus comprising a photoelectric transducer element for receiving light reflected by at least one of the surfaces of a shutter blind and a film, and an operational amplifier for biasing the photoelectric transducer element to maintain the voltage applied thereacross substantially null, thereby enabling a photometric output of the photoelectric transducer element to be effectively derived even when the amount of light received is minimal. The shutter blind is provided with a surface upon which at least two portions thereof have different coefficients of reflectivity to reduce adverse effects of reflected light upon the desired exposure period.

A photometric apparatus for single lens reflex camera and of the type in which an exposure value is determined by photometry of light which is transmitted through a photographic optical system and is reflected by at least one of the surfaces of a shutter blind and a film, said apparatus comprising a photoelectric transducer element for receiving light reflected by at least one of the surfaces of a shutter blind and a film, and an operational amplifier for biasing the photoelectric transducer element to maintain the voltage applied thereacross substantially null, thereby enabling a photometric output of the photoelectric transducer element to be effectively derived even when the amount of light received is minimal. The photometric apparatus, including a photoelectric transducer element, a photometry switch and associated circuitry are mounted upon a printed circuit board mounted within the camera to position the transducer element to receive reflected light from the film or the shutter.

A photometric apparatus for single lens reflex camera and of the type in which an exposure value is determined by photometry of light which is transmitted through a photographic optical system and is reflected by at least one of the surfaces of a shutter blind and a film, said apparatus comprising a photoelectric transducer element for receiving light reflected by at least one of the surfaces of a shutter blind and a film, and an operational amplifier for biasing the photoelectric transducer element to maintain the voltage applied thereacross substantially null, thereby enabling a photometric output of the photoelectric transducer element to be effectively derived even when the amount of light received is minimal.

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Hachioji, Japan

Masahiro Kitagawa