Abstract: A camera system has a film cartridge provided with a first shaft around which an unexposed film is wound, a second shaft for taking up an exposed film and a movable third shaft which causes a portion of the film which has been sent out from the first shaft to be folded back in a U-turn way so that the portion of the film is allowed to be taken up around the second shaft, and a camera capable of being loaded with the film cartridge and provided with a moving mechanism for moving, when the film cartridge has been loaded, the third shaft of the film cartridge so as to make an exposure.

Abstract: An optical type encoder, which detects a light beam from a light source by a light receiver through a plurality of slit arrays of a gauge member provided to an object to be detected, and detects position information of the object to be detected by utilizing a signal from the receiver, is disclosed. The light receiver includes a plurality of sensors which are arranged in a direction parallel to a position detection direction and are capable of detecting the incident position of a light beam. The plurality of slit arrays of the gauge member are arranged in correspondence with the plurality of sensors, so that a plurality of slits of each slit array are aligned in the position detection direction. All the positional relationships between the corresponding slits in one slit array and the other slit array of the plurality of slit arrays are different from each other.

Abstract: A data imprinting device for a camera of the kind permitting change-over from one photo-taking image plane size to another is arranged to vary the size and/or position of imprinting data according to the change-over of the image plane size.

Abstract: A motor driven camera for winding and rewinding film by an electric motor includes a mechanism for detecting the end of a length of loaded film to produce an actuating signal. An automatic changeover mechanism responds to the actuating signal by changing the state of a film transport mechanism in the camera from a film winding operating mode to a film rewinding operating mode. The automatic changeover mechanism is arranged to be operated in response to closing of the back cover of the camera. Accordingly, the transition from the winding to the rewinding operating modes is controlled automatically.