| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a media tilt compensation apparatus performing proper tilt compensation by highly accurately detecting the tilt of the beam spot position of an optical recording medium with high sensitivity and by simple structure free from the problem of cost increase. <P>SOLUTION: Tilt compensation is performed based on radial tilt and tangential tilt calculated from radial tilt obtained by partially differentiating the height Ψ (r, θ) of an objective lens at the time of focusing on an optical recording medium and tilt in a track tangential direction. For example, a plurality of tangential tilt are sampled at a predetermined radial position, a sampled value is subjected to Fourier transformation, the DC component of a tilt compensation current, the imaginary and real parts of a 1ω component, and the imaginary and real parts of a 2ω component are obtained by a simple Fourier transformation operation using a determinant and, based on obtained data, the tilt of the optical recording medium is highly accurately compensated. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
