| 摘要 |
PROBLEM TO BE SOLVED: To make difficult the occurrence of interference of detecting signals with each other between grooves adjacent to each other by forming the grooves having depths, while using the lands as references, to be alternately changed and having constant widths in accordance with a modulated signal obtained by modulating a signal for the rotary servo of an optical disk with an address signal between recording tracks on the land. SOLUTION: Between adjacent lands LD0, LD1,..., where recording tracks T0, T1,..., are formed, grooves GV0, GV1,..., are formed to have depths, while using the lands LD0, LD1,..., as references, to be alternately changed to be βand γ nm (0<β<γ) in accordance with a modulated signal obtained by modulating a signal for the rotary servo of an optical disk with an address signal. By changing the depths β and γ, the amplitudes of detecting signals detected from the grooves GV0, GV1,..., by an optical head are varied. When the wavelength of a laser beam from the optical head is regarded as λ, crosstalk is reduced by making the difference of depths (γ-β) to be λ/6. |
