| 摘要 |
PURPOSE:To enable rewriting, by setting a tracking light beam in advance of an erasing light beam and therefore using the track itself which performs the recording and reproduction to the tracking purpose. CONSTITUTION:It is possible to perform the accurate tracking even though a recording track is erased, by giving the tracking to the tracks, e.g. adjacent tracks other than that which performs erasion and rerecording on a disk surface 20. That is, the tracking is carried out by the light beams 1 and 3 which are set to hold a reproducing beam 2 between them in the moving direction of the disk. The erasion and rerecording are carried out by beams 4 and 5, respectively. In such way, a tracking itself which performs recording and reproduction is used to the tracking purpose to enable rewriting. |
