INFORMATION RECORDING MEDIUM AND MASTER EXPOSING DEVICE

• Main Authors: SASAKI HIDEHIRO, KIYONO KENJIRO, KUBO MASAE
• Format: Patent
• Language: English
• Published: 30.10.2008
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

PROBLEM TO BE SOLVED: To realize stable focus servo and tracking servo in an information recording medium having a plurality of recording regions of different track pitches and groove shapes. SOLUTION: A recording track formed by a convex/concave pattern includes first and second recording regions R1 and R2 and a recording region transition section Sx arranged between the first and the second recording regions R1 and R2. The first recording region R1 has a track pitch tp1, a groove width w1, and a groove depth d1 and the second recording region R2 has a track pitch tp2, a groove width w2, and a groove depth d2. These track pitches, the groove widths, and the groove depths satisfy prescribed expressions. The recording region transition section Sx includes a track pitch transition section where the track pitch changes from tp1 to tp2 and a groove shape transition section where the groove width changes from w1 to w2 and/or the groove depth changes from d1 to d2. The track pitch transition section and the groove shape transition section share at least a partial region. COPYRIGHT: (C)2009,JPO&INPIT