Patent ID: 7194749

Claim:
An objective lens actuator capable of moving an objective lens at least in a focusing direction and performing tilt correction, the objective lens collecting beams on an optical information storage medium for reading/writing information on the optical information storage medium, said actuator comprising: an objective lens holder holding the objective lens; a base body supporting the objective lens holder to enable a motion of the objective lens holder at least in a focusing direction and tilt correction; and a drive unit exerting a drive force on the objective lens holder, wherein: the drive unit includes a set of magnets mounted to the base body and a set of coils mounted to the objective lens holder; the set of magnets includes a pair of a common magnet and a divisional magnet, the pair facing each other across a gap and forming a magnetic circuit generating magnetic flux extending from either one of the common magnet and the divisional magnet to a remaining one, the divisional magnet including a first magnet and a second magnet; the set of coils including a focusing coil and two tilting coils, the focusing coil being disposed so that: a winding thereof cuts across the magnetic flux; the common magnet exists outside the winding; and the first and second magnets exist inside the winding, the focusing coil, when energized, generating a drive force in a focusing direction, the two tilting coils being each disposed so that: a winding thereof cuts across the magnetic flux; the common magnet exists outside the winding; either one of the first and second magnets exists inside the winding; and a remaining one of the first and second magnets exists outside the winding; the two tilting coils, when energized, generating a drive force for tilt correction.