A stopper 30 includes a projected portion 35 for restricting movement of a movable section in a focusing direction and a wall section 34 for restricting movement of the movable section in a tracking direction, the projected portion 35 and the wall section 34 being integrally formed from a synthetic resin. With the arrangement, a single stopper 30 can simultaneously restrict the movements of the movable section both in the focusing direction and the tracking direction and determine its movable ranges. Accordingly, unlike conventional arrangements, discrete stoppers for the focusing direction and the tracking direction do not have to be provided, thereby reducing the number of components and cost as well as facilitating mounting operation. In addition, even when a strong impact is applied, the stopper will not be deformed.