Patent ID: 7194748

Claim:
An objective lens driver comprising: a support base formed of a magnetic material, comprising a base portion, a support shaft projected from said base portion, and a pair of yokes respectively projected in the same direction as said support shaft from both side edges of said base portion and located oppositely to each other with said support shaft therebetween, said yokes having opposed surfaces to which magnets are fitted; a movable portion supported on said support shaft of said support base so as to be turnable around an axis of said support shaft and slidable in the axial direction of said support shaft, holding an objective lens having an optical axis substantially coinciding with the axial direction of said support shaft, and comprising a focusing coil supplied with a driving current at a time of focusing control of laser light radiated onto a recording medium through said objective lens, and at least a pair of tracking coils supplied with a driving current at a time of tracking control of said laser light; and a magnetic member formed in a roughly ring form, comprising a pair of projection portions maximum in outside diameter with a central portion therebetween, and fitted to said movable portion, said pair of projection portions being respectively attracted toward central portions of said magnets so as thereby to hold said movable portion in a neutral position in a focusing direction and in a tracking direction, wherein said magnets, said yokes, said base portion, and said support shaft form a magnetic circuit.