Patent ID: 8315141
Filing Date: 2012-11-20
Classification: G11B

Abstract:
1. An objective lens driving apparatus comprising: a base opposed to a signal surface of an optical disc; an objective lens holder including an objective lens, first and second focusing coils arranged in line with the objective lens in a tracking direction of the optical disc, first and second tracking coils arranged in line with the first focusing coil in a tangential direction of the optical disc, and third and fourth tracking coils arranged in line with the second focusing coil in the tangential direction, the objective lens holder being supported on the base movably in a focusing direction of the optical disc and in the tracking direction; and first to fourth magnets arranged on the base so as to be respectively opposed in the tangential direction to the first to fourth tracking coils, each magnet comprising: a first pole portion that is magnetized to a first pole; and a second pole portion that is magnetized to a second pole opposite in polarity to the first pole, wherein, for each of the first to fourth magnets: