A driving device for an ultrasonic actuator for driving a movable member
is provided with a member sensor for detecting a present position of the
movable member, a calculator for calculating a control target position of
the movable member, a driving circuit for generating such a drive voltage
as to drive the ultrasonic actuator in a specified resonant state, and a
control circuit for controlling an operative state of the movable member
by adjusting at least one of physical quantities specifying the drive
voltage as a maneuverable physical quantity in accordance with a
difference between the present position and the control target position
so that the movable member pursues the control target position. There can
be provided a driving device capable of executing a position servo
control while being driven in a specified resonant state, and a position
controller and a camera provided with such a driving device.