| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical recording medium for recording data with a density higher than that of a DVD read-only optical disc and recording medium identification information securing a sufficient defocus margin using a conventional medium identification information recording device. <P>SOLUTION: The optical recording medium has a main information region 21 in which a metal reflection film is formed on a substrate on which a pit row is formed as main data and a sub-information region 22 in which medium identification information 23 for individually identifying the optical recording medium is recorded by partially removing the metal reflection film to form a plurality of reflection film removed regions. Information is reproduced from the optical recording medium by irradiating the metal reflection film with a light beam. A pit row or a guide groove is formed on the substrate in the sub-information region, and has a track pitch of 0.24 to 0.45 μm. <P>COPYRIGHT: (C)2009,JPO&INPIT |
