PURPOSE: To improve operability of motion of an image by a joy stick.

CONSTITUTION: A device is provided with a control means having a continuous motion mode in which an image moves continuously while a joy stick 8 to indicate motion of the image in a CRT is set down, and a relative position mode in which the image moves for quantity in proportion to an angle of the joy stick 8 when it is set down from a center position, and then stops. When a mode changing switch 8a for changing these two modes as desired selects the relative position mode, motion of the image is prohibited if the joy stick 8 moves from a condition of being inclined to the center position toward the center position. The control means is provided with a function of allowing motion of the image when the joy stick 8 returns to the center position.