Patent ID: 7406007

Claim:
An optical disc apparatus, comprising: an objective lens for focusing a light beam on an information surface of an optical disc, the optical disc being at least reproduced optically; an objective lens moving section for moving the objective lens in relation to the information surface; a focus error signal generating section for generating a focus error signal indicating a focused state of the light beam focused on the information surface; a focus control section for controlling the objective lens moving section to focus the light beam on the information surface in accordance with the focus error signal; a lens tilting section for tilting the objective lens to correct coma aberration occurring in a light beam spot focused on the information surface, wherein the lens tilting section generates a tilt control signal based on the tilt of the objective lens; a spherical aberration signal generator for generating a first spherical aberration correction signal based on light detection occurring in the light beam spot focused on the information surface; a lens tilt-spherical aberration correction control section which receives the tilt control signal and the first spherical aberration correction signal, and generates a second spherical aberration correction signal by modifying the first spherical aberration correction signal by an amount based on a predetermined relationship between the tilt control signal and a resultant lens tilt spherical aberration; and a drive section for correcting spherical aberration that receives the second spherical aberration correction signal to drive at least one spherical aberration correction lens.