| 摘要 |
PROBLEM TO BE SOLVED: To obtain the highly reliable discrimination result with respect to eccentricity, noise due to a pit formed on a land part, noise due to a recording mark, etc,. in an optical disk playing back device for discriminating the recordable optical disk having the meandering groove and the optical disk exclusively used for the playback by the meandering of the groove. SOLUTION: The device is constituted in such a manner that a linear velocity is controlled so as to obtain the linear velocity expected to detect the meandering frequency of a data recording track by the frequency different from a center frequency of a band-pass filter, and the maximum and minimum values in the result of the measurement made by a period measuring counter in the set measuring period are calculated, and when the maximum and minimum values exist within the specific range, it is discriminated that the data recording track is meandering for the specific period. COPYRIGHT: (C)2003,JPO
|
