| 摘要 |
PURPOSE:To eliminate double transfer and to improve a tracking signal by providing plural tracks of grooves and pits to the inside and outside circumferences is proximity to a track region having sample marks. CONSTITUTION:The groove regions 34, 36 which are Miller regions are respectively provided at about 1mm while on the inside and outside circumferences near the sample mark region 32 on a substrate 2 made of polycarbonate. The sample mark pits 10, 11 and the pits 12 for clock are provided to the sample mark region and the grooves 3 are provided to the boundary between the region 32 and the groove region, respectively. The grooves 3 provide an anchor effect at the time of injection molding of the substrate to prevent the generation of the double transfer. The tracking is, therefore, stabilized. |
