Electrical information transmission system for photographic camera - provides objective identification and data exchange between camera and objective

摘要

The transmission system is used for supplying information from the camera objective to the automatic exposure control. At least one transmission channel has a bidirectional circuit (3) on the camera side, coupled to a high-ohmic current source (12) on one side and to a central processor (2) on the other side for identifying the objective and for data exchange with the latter. The objective incorporates a voltage divider converting the signal provided by the bidirectional circuit (3) and the current source (12) into a given level identifying the objective, for feeding back to the central processor (2).