Abstract: Active lens components are provided for transmitting to a corresponding photographic camera information from a photographic field lens which is transformed into electrical signals. These components transform the information into electrical signals, the properties of which are convertible. The signals are transmitted to an evaluating circuit in the camera either serially via a contacting device or according to a predetermined chronological sequence. The evaluation circuit is provided with means by which the original information is gained back from the signals. The signals resulting from the recovery are fed to display means and/or to control arrangements for additional camera functions. The contact for the transfer of information is also employed as a power supply contact.

Abstract: The camera includes a disengageable safety retaining catch for interchangeable lens objectives and an automatic focusing mechanism connected to a drive shaft for the transmission of rotary adjustment setting motions to the lens objective. The drive shaft operationally engages the automatic focusing mechanism via a drive and is provided with a spring supported in the axial direction. The rear end of the drive shaft is guided in a fixed bearing bushing. The front end is supported in a connection flange on the camera body. The front end is formed as a claw or toothed coupling element protruding beyond the connection flange and engages a complementary coupling piece which is disposed in a connection base on the lens objective.

Abstract: A device for focusing an optical system which consists essentially of a guide cylinder and a coaxial tube guided inside or onto the cylinder and containing at least a portion of an optical system. The guide cylinder and the tube are relatively displaced by a rotational motion converted into a linear motion for the purpose of focusing.The relative displacement between the guide cylinder and tube components (1,2) of the device are produced according to principles practised with ball thread spindles. For complying thereto each component is provided with a guide groove (3,4) helically winding around the axis of rotation (5) of each component (1,2). One of the components (1,2) is provided with a return channel (6) connecting at least two consecutive turns of the guide groove (3).

Abstract: Disclosed is a reduction gear assembly for automatically accommodating varying load conditions on a driven member, comprising a rotatably mounted, axially displaceable first shaft; a drive engagement driving the first shaft by a frictional force engaging in the axial direction of the shaft; a driving element mounted for rotation with the first shaft; and a driven member rotatably driven by the driving element and being subjected to varying load conditions, wherein the driving element comprises means for controlling the axial movement of the first shaft in response to the varying load conditions on the driven member. Also disclosed is a camera embodying the reducing gear assembly as part of an automatic film advance system.