PURPOSE: To reduce blur quantity by a small quantity of rotating operation of a focus ring when zooming is performed to a telephotograph side after focus adjustment is performed at the wide-angle end by making a control circuit have a function which varies driving quantity of a focus motor by rotating quantity of a focus ring in accordance with conditions of a zoom switch.

CONSTITUTION: This device is provided with a zoom motor control circuit 13 which detects conditions of a zoom switch 1 and controls a zoom driving circuit 11, a focus motor control circuit 15 for zoom tracking which controls a focus motor 10 for zoom tracking, and a focus motor control circuit 14 for focus ring which controls a focus motor 10 by a focus ring 3. And a driving quantity changeover switch 17 and a variable amplifier 18 are provided, conditions of the zoom switch 1 is detected, focus driving quantity is switched, and driving quantity is varied.