A control circuit generates a driving signal indicating an actuator torque. A first operation unit generates position, speed, and acceleration signals, based upon a detection signal indicating the actuator mover state. A second operation unit generates a first difference signal indicating the difference between a target signal and the position signal. A third operation unit generates a second difference signal indicating the difference between signals based on the first difference signal and the speed signal. A fourth operation unit generates a position control signal such that the second difference signal becomes zero. A fifth operation unit generates a third difference signal indicating the difference between signals based on a driving signal and the acceleration signal. A sixth operation unit generates a driving signal by summing a signal based on the position control signal and a disturbance estimation signal based on the third difference signal.