Patent ID: 6337845
Filing Date: 2002-01-08
Classification: G11B

Abstract:
An optical disk medium comprising:groove tracks formed annularly on the disk and land tracks formed between the groove tracks, a groove track and a land track each corresponding to one revolution of the disk medium, the land and groove tracks being alternately connected to each other at connecting points to form a continuous recording spiral, each track having an integer number of recording sectors of equal length, an identification signal area containing an identification signal representing address data being provided at a leading end of each recording sector, and being radially aligned with an identification signal area of an adjacent recording sector; wherein the identification signal of each recording sector is embossed in such a way that a polarity of a differential signal from a first part of the identification signal area is opposite to a polarity of a differential signal from a second part of the identification signal when a light spot scans the center of a corresponding track, and at least one of the first part and the second part of the identification signal area further contains tracking polarity information for the corresponding recording sector, said tracking polarity information indicating whether the corresponding recording sector is at the connecting point between radially adjacent land and groove track revolutions so as to indicate when tracking polarity should be changed.