| 摘要 |
PURPOSE: To record bits having different longitudinal dimension but almost same width dimension by forming a synthetic resin recording double layer, incorporating a dye which absorbs the laser beam used into the first and second synthetic resin layers, and using laser beams of a high energy level and a low energy level. CONSTITUTION: The recording double layer 4 consists of an expanding layer 2 and a holding layer 3, and the recording double layer 4 is exposed to laser beams 5. The first and second synthetic resin layers 2, 3 contain a dye which absorbs the laser beams 5 used. By using the laser beams 5 of a high energy level and a low energy level, bumps 6 are formed in the recording layer 4 by allowing to expose with the laser beams 5 of a low energy level, and bumps 7 having grooves 8 on the surface are formed by allowing to expose with the laser beams 5 of a high energy level. Thus, information can be recorded while maintaining the width size of bumps 6, 7 almost same. |
