Abstract: An electromagnetic actuator for driving a movable plate equipped with an optical element such as a mirror on the basis of the operation principle of a galvanometer. The structure of the movable plate is simplified, and a driving coil and a wiring are formed by aluminium vapor deposition to improve durability. When an impact brings the movable plate outside the allowable rocking range of the movable plate, a stopper prevents excessive displacement of the movable plate to thereby prevent destruction of a torsion bar that supports the movable plate. Moreover, electrical connection in the torsion bar is eliminated to prolong the service life, and a production process is simplified to reduce a production cost.