JPS6490410A - Zoom lens - Google Patents

Abstract

PURPOSE:To obtain a miniature and light zoom lens by which zooming and focusing can be executed exactly in a short time by inputting signals from the respective command means for instructing a movement of a variable power lens group and an image forming lens group, to an arithmetic circuit and outputting each set position signal. CONSTITUTION:When a command is given to an arithmetic circuit 7 by operating a command means 6 in order to adjust the focus, the arithmetic circuit 7 outputs a set position signal to a setting means 9, based on this command. The setting means 9 moves an image forming lens group 4 to a position which has been instructed by the set position signal and allows it to stand still, by which focusing is completed. At the time of executing a zooming operation, when a command is given to the arithmetic circuit 7 by a command means 5, a variable power lens group 2 moves by the set position signal outputted to a setting means 8 from the arithmetic circuit 7, and simultaneously, the image forming lens group 4 moves by the set position signal outputted to the setting means 9 from the arithmetic circuit 7, by which focusing is executed.