| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform layer jump always safely and surely in a blue ray disk. <P>SOLUTION: By an acceleration/deceleration pulse 300 superimposed on a focus control signal 200 controlling a position of a condensed spot of a laser beam, for example, from L0 to L1, timing at which the condensed spot of the laser beam is jumped to a recording layer of a target is made always constant by superimposing the acceleration/deceleration pulse 300 on the focus control signal 200 at a point of time at which a fixed time (t) elapses from a rotary synchronizing signal 400 synchronizing with rotation of an optical disk (blue ray disk). Thereby, even if wobbling or the like of the blue ray disk is large, layer jump is performed always safely and surely. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
