Abstract: A power supply system for a camera supplies electrical power to a light measuring circuit, a display circuit and others. During a hold state before the camera turns into a standby state, the power supply system supplies a boosted electrical power intermittently to the light measuring circuit, the display circuit and others, so that photographic information such as shutter speed and aperture value based on the measurement of the light measuring circuit are displayed on a display and power consumption in the hold state can be made small.

Abstract: A data rewriting apparatus for a photographic camera, which comprises a film speed reading unit for automatically reading the film speed recorded on a container of a film in use; a first memory including RAM for the storage of the film speed; a second memory including E.sup.2 PROM for the storage of the film speed; a rewriting unit for rewriting a value stored in the first memory to a value stored in the second memory; a comparator for comparing the value stored in the second memory with that stored in the first memory; and a rewrite control unit for inhibiting the rewriting of the second rewriting unit when the comparator indicates that the value stored in the second memory is identical with that stored in the first memory.

Abstract: A photographic camera system having a camera and an electronic flash device detachably attached to the camera. The electronic flash device includes an operational member for outputting a control signal in response to a manual operation and a first group of terminals for electrically connecting the electronic flash device to the camera and for providing a control signal therethrough. The camera includes a second group of terminals electrically connected to the first group of terminals, an input section for inputting the control signal through the second group of terminals, a circuitry for carrying out preparatory operation for a photography, and a control circuitry for energizing the circuitry in response to an input of the control signal to the input section.

Abstract: A camera is provided with a camera data input/output device which operates selectively to read the film data of a film cartridge and to receive and output the camera checking data through a group of terminals provided in a film chamber accommodating the film cartridge and a part of an external device detachably attached to the camera body. In response to a control signal input from the external device, the camera checking data are exchanged between the camera body and the external device, and the film data are received with the film cartridge loaded in the film chamber.

Abstract: A control device for use in a camera for driving two electric motors has a simple circuit arrangement in which one of three serial circuits having series connected transistors is commonly used for selectively driving the two electric motors in turns. In addition, for driving electromagnets and motors, the control device includes a CPU for generating m bits control data and a decoder driver IC for decoding the n bits control data into a m bit signals which selectively drive the electromagnets and the motors, wherein n is smaller than m, so that the number of control signal lines needed for the transmission of the control data from the CPU to the decoder driver IC can be reduced.

Abstract: In a data transmission system for a camera, a central processing unit (CPU) for controlling operation of the camera communicates with various circuit arrangements using data signals in a serial form under control of a clock signal selected in dependence upon which the circuit arrangement is the communication designation of the CPU at the time. Some of the circuit arrangements are provided in the camera while the other of the circuit arrangements are provided in accessories attachable to the camera. The CPU communicates with the circuit arrangements provided in the camera under control of a clock signal having a higher frequency for increasing the data communication speed while it communicates with the circuit arrangements provided in the accessories under control of a clock signal having a slower frequency for improving the accuracy of the data communication.

Abstract: A data rewriting apparatus for a photographic camera, which comprises a film speed reading unit for automatically reading the film speed recorded on a container of a film in use; a first memory including RAM for the storage of the film speed; a second memory including E.sup.2 PROM for the storage of the film speed; a rewriting unit for rewriting a value stored in the first memory to a value stored in the second memory; a comparator for comparing the value stored in the second memory with that stored in the first memory; and a rewrite control unit for inhibiting the rewriting of the second rewriting unit when the comparator indicates that the value stored in the second memory is identical with that stored in the first memory.

Abstract: In a camera system effective use of a single microcomputer for both automatic exposure control and automatic focus control is made possible by designing the microcomputer so that it repeats calculation for the automatic exposure control during time period for charge accumulation in a CCD focus detection sensor and during lens focusing movement and so that it performs calculation for the automatic focus control while interrupting the calculation for the automatic exposure control upon the ending of the charge accumulation in the CCD focus detection sensor and upon shifting of the lens by an amount predetermine based on the result of the calculation for the automatic focus control.

Abstract: A camera of the multi-program mode type wherein a suitable program mode is selected properly in accordance with given conditions of the camera. The camera comprises a display device which displays a program mode selected by a manually operable means. When a normal program mode is selected, a microcomputer receives focal length information of an interchangeable lens mounted on the camera and automatically selects one of program lines provided for the normal program mode in accordance with the received information. Meanwhile, the microcomputer enables selection of a macro photographing program mode only when focus adjusting of the interchangeable lens is within a macro range.

Abstract: A control device for use in a camera system makes it possible for the camera system to effect a high speed consecutive photographing only by repeated depression of a shutter release button. The control device also makes it possible for the camera system to effect a low speed consecutive photographing when the shutter release button is kept depressed.

Abstract: A camera with a barrier wherein a photograph with proper exposure can be produced without taking anything into consideration so far as the barrier is closed and change-over of an operation mode of the camera can be effected automatically in response to a position or a motion of the barrier. The barrier is mounted for movement between an open position in which an operable member operable for reflecting intention of a photographer on exposure is exposed to allow operation of the operable member and a closed position in which the barrier covers the operable member. When the barrier is in the open position, an exposure controlling mode in which intention of a photographer is reflected on exposure can be selected, but when the barrier is in the closed position, the intention of the photographer is prevented from being reflected on exposure.

Abstract: An electronic flash device, detachably attached to a photographic camera, comprising a circuitry for carrying out preparatory operation for a flash photography, an input section for receiving a first start signal from the photographic camera and for outputting the same, signal outputting means responsive to a manual operation for outputting a second start signal, and power supply hold means connected to the circuitry, the input section and to the operational member.

Abstract: An exchangeable lens includes a lens system which forms an image of a target object on which the lens system is focused, a focus adjusting means manually operable for adjusting the focus of the lens system, a direction signal generating means which generates a direction signal representing the relationship between the operational direction of the focus adjusting means of the lens and change of the camera-to-object distance to be focused on by the lens system and a transmitting means which transmits the signal to a camera on which the exchangeable lens is detachably mounted.

Abstract: A camera accessory such as an exchangeable lens or an electronic flash device, selectively attached to a camera and having a driven member and an encoder for the driven member. The encoder having a pattern for position adjustment and a brush linked with the driven member, the encoder being constructed to produce code data indicative of the position of the brush on the pattern. The camera accessory outputs a signal indicative of a relationship between the driven member and encoder on the basis of the data from the encoder, the signal being used for the position adjustment.

Abstract: An exchangeable lens to be mounted on a camera body by the rotation of the lens barrel is provided with a plurality of terminals arranged circularly along the circumference of the lens barrel about the optical axis of the lens barrel and are connected to a CMOS circuit in the lens. The terminals include a power supply terminal and a ground terminal through which electric power is supplied from the camera and a signal terminal through which a signal is transmitted between the camera body and the lens. The power supply terminal and the ground terminal are arranged to come into contact with their corresponding camera terminals in advance of the signal terminals when the lens is rotated to mount it on the camera body.

Abstract: A photographic camera provided with a focus detecting system having a device for periodically sensing a focus condition of the camera to repeatedly produce a signal in response to every periodical sensing of the focus condition so as to effect the focus detection according to the signal from the sensing device.

Abstract: Accessories for use in photographic camera systems provide various data that are inherent to the objective lens being used and are transmitted from the objective lens to the camera body, and the various data are processed and the resultant data are used for automatic exposure control, automatic focusing, and various warnings and indications. Such data may include the maximum and minimum F-numbers, the focal length and the shortest photographable distance of the lens, data indicative of the relationship between the direction of the rotation of a motor within the camera body for automatic focusing and the direction of movement of the lens system, and data indicative of the relationship between the amount of rotation of the motor and the amount of the shifting of the image plane.

Abstract: A camera acoustic indicating device for indicating, by sound, attainment of an in-focus condition of a camera objective lens and warning possibility of a blur occuring exposure time due to low brightness of an object to be photographed. The sound for the in-focus indication is intermittently generated at a frequency higher than that at which the sound for the blur warning is intermittently generated. When the attainment of an in-focus condition is detected while the blur warning is being made, the warning is interrupted for a given time period during which the attainment of the in-focus condition is indicated for a short time.

Abstract: Disclosed herein is an automatic focusing device of a camera for use with an exchangeable zoom lens which includes an objective adjustable for both focusing and zooming and a signal generator for generating a focal length signal. The automatic focus control device comprises a focus detector for generating a focus detecting signal .DELTA.L representing the amount of and the direction of the deviation (defocusing) of an image relative to a predetermined film plane, a motor driven for focus adjustment of the objective, and an operation circuit for determining the amount of and the direction of the driving of the motor in accordance with the focus detection signal and the focal length signal.