<p>A collision preventive member 9 that limits displacements of an objective lens 1 in a focusing direction F is provided. The collision preventive member 9 includes a first limiting portion 9f that limits displacements of the objective lens 1 present within a first region A1 while allowing a movable range of the objective lens 1 in the focusing direction F to overlap a deflection range of the optical disc within the first region A1, and a second limiting portion 9g that limits displacements of the objective lens 1 present within a second region A2 in establishing a relation such that the movable range of the objective lens 1 in the focusing direction F does not overlap the deflection range of the optical disc within the second region A2. A controller that controls the objective lens 1 in such a manner that the objective lens 1 is located within the second region A2 in a non-focusing state of the objective lens 1 is provided. It is thus possible to prevent a collision between an optical disc and the objective lens under the environment where vibrations are applied.</p>
