| 摘要 |
PURPOSE:To obtain the control signal of recording data in accordance with clock information and timing information at the time recording by adding above- mentioned information by the information on the displacement in a transverse direction smaller in the displacement than the information on the displacement in the transverse direction. CONSTITUTION:Pregrooves (ROM tracks) 1b are formed in a reproduction only region 1B and pregrooves (ROM tracks) 1a are formed in a recordable region 1A. The displacement DELTAd1 in the transverse direction is applied to the ROM tracks 1b at the time of mastering of an optical disk and the ruggedness (the information on the displacement in the transverse direction) of the displacement DELTAd1 in this transverse direction is formed. The similar displacement DELTAd2 in the transverse direction is formed in the RAM tracks 1a as well. The displacement DELTAd2 in the transverse direction formed in the RAM tracks 1a can apply mainly the clock information and is preferably formed as the information on the displacement in the transverse direction to form ruggedness in 17 bit unit so as to allow the easy extraction of the clock frequency (4.3218 MHz) adopted in, for example, a CD format. The good tracking control is executed in this way. |
