Patent ID: 7619951

Claim:
An optical actuator, comprising: a base; a lens holder movably installed on the base by a support member and mounted with an objective lens to transmit an incident light to an optical information recording medium; and a magnetic circuit to independently drive the lens holder in a focusing direction, a tilting direction and a tracking direction, respectively, wherein the magnetic circuit comprises: a first and second focusing coil installed on an inner surface of the lens holder in the tracking direction, a tilting coil installed on an inner surface of the lens holder, the tilting coil being layered with the first and second focusing coils in the focusing direction, a pair of tracking coils installed on an outer surface of the lens holder, the pair of tracking coils being arranged in parallel to the tracking direction, a first magnet part, arranged on a first side of the lens holder, in which magnet polarities oppose each other, a second magnet part, arranged on a second side of the lens holder, the second side being opposite the first side, so as to be parallel with the first magnet part, in which magnet polarities opposite corresponding magnet polarities in the first magnet part, a first pair of inner yokes surrounded by the first focusing coil, a second pair of inner yokes surrounded by the second focusing coil, a third pair of inner yokes between the first and second focusing coils and surrounded by the tilting coil, and outer yokes outside of the focusing coils and tilting coil.