DISTANCE INFORMATION OUTPUT DEVICE FOR INTERCHANGEABLE LENS

摘要

PURPOSE:To permit forcusing with high accuracy and to obtain distance information of a lens as information on a rotating quantity detector by using a CPU provided on a lens barrel side and the rotating quantity detector. CONSTITUTION:A distance ring 201 of an interchangeable lens is turned to an infinite position or extremely short distance position by an extreme position setting means 502 substantially at the same instant when the lens barrel 200 of the interchangeable lens is mounted to a camera body 100 or a power supply device is mounted thereto. The distance information is then obtd. by the rotating angle of the distance ring 201 from such reference position. The CPU211 which is an arithmetic processing unit of a microcomputer contg. the data necessary for the focus control of the individual interchangeable lenses as part of program outputs the absolute distance information of the interchangeable lens by data and electric pulses to the CPU111 in the body 100 after the distance ring 201 is set to the infinite position or extreme short distance position which is the reference position of the interchangeable lens. The distance is set by a driving means 501 provided in the lens barrel 200 or the body in accordance with the output.