| 摘要 |
PROBLEM TO BE SOLVED: To suppress the error rate of a data signal low by eliminating a reading error caused by the difference of an optical condition due to the existence of a land pre-pit showing address information in optically reading a recorded signal. SOLUTION: The shape of a groove-shaped tracking guide 3 is made to be different from the other part in a part adjacent to the land pre-pit 6 provided on a land 8 showing the address information. Concretely, the depth or width of the tracking guide 3 of the part adjacent to the land pre-pit 6 is changed. Thus, the difference of the optical condition due to the existence of the land pre-pit 6 is adjusted and modified. The land pre-pit 6 is also offset from the center of the land 8 to the inner peripheral side of a light-transmitting substrate 1. |
