| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an information recording medium, capable of obtaining satisfactory reproduction information both from a reproduction exclusive pit line and from a recording reproduction guide groove, and also regularly obtaining optimum tracking characteristics both in an unrecorded area and in a recorded area by reproducing an intermediate area including a pit line by a differential push-pull tracking method or a phase difference method. <P>SOLUTION: The information recording medium in which bottoms of a guide groove and a pit line formed on a disc substrate are allocated on a same flat plane and shaped in flat. Further, in a transition area from a pit line to a guide groove or from a guide groove to a pit line, the information recording medium includes an intermediate area composed of a pit line of which height changes from a height between a bottom and a side of a groove to another height between the bottom and a side of the pit line. <P>COPYRIGHT: (C)2008,JPO&INPIT |
