Optical data recording/reproducing apparatus

摘要

An optical data apparatus for recording and regenerating data on an optical disc, optical card, or the like is capable of detecting a tracking error signal with an optical data storage medium on which optical data is recorded at a high density. A pattern is formed on a track and in a position displaced from the track by half cycle of the track in a first servo pattern area (SPA1), and no pattern is formed in a second servo pattern area (SPA2). The first servo pattern area (SPA1) and the second servo pattern area (SPA2) are arranged adjacent one another. The tracking error signal is obtained through multiplication of differential signals obtained at the timing of Sa1 and Sa2. The tracking error signal can be detected up to a spatial cutoff frequency twice as high as the frequency in the conventional case by means of a conventional optical system.