| 摘要 |
The invention relates to an optical scanning device which operates on the triple-beam principle. In a known optical disk, the data tracks are wobbled about a mean frequency. However, it is more difficult for the scanning light beam to track the wobbled data tracks. To facilitate tracking by the main beam (L1) which scans the data in an optical disk with a wobbled data track, the distance between the +1 level diffracted beam (L2) and the -1 level diffracted beam (L3) on the disk is chosen to be an integral multiple of the wavelength T of the wobbled track. The invention is applicable to reproducing devices for optical disks with a wobbled data track. |
