| 摘要 |
<P>PROBLEM TO BE SOLVED: To speed up an access to a recording layer of an optical disk. <P>SOLUTION: A servo DSP 16 controls an optical pick-up 7. The optical pick-up 7 is provided with a semiconductor laser 4, an actuator 3 for changing a focus position of an optical beam from the semiconductor laser 4, and a collimator lens driving mechanism 27 for correcting spherical aberration by moving the collimator lens 26 in an optical axial direction. The servo DSP 16 starts to control the actuator 3 while changing the collimator lens 26 to a correction position of the spherical aberration corresponding to a recording layer of the optical disk 1 and controls the collimator lens driving mechanism 27 on the basis of an aberration error signal of the spherical aberration generated by using a signal from an optical detector 6. <P>COPYRIGHT: (C)2008,JPO&INPIT |
