| 摘要 |
PROBLEM TO BE SOLVED: To make an optical disk to switch tracking according to the groove depth by providing the groove depth information of a recording track on control track information. SOLUTION: A beam is radiated from an optical head 102 toward the optical disk 101, a reflection beam from the optical disk 101 is received again by a quadripartite light receiving part in the optical head 102 and the light quantity is converted into an electric signal to be outputted to a preamplifier 103. In the preamplifier 103, a sum signal becoming the origin of regenerative data, the focus of the optical head, a focus error signal becoming a position error of tracking and a servo error signal being a tracking error signal are generated from the electric signal from the light receiving part and the signal is outputted to a polarity reverse means 108. The sum signal is inputted to a reproducing means 104 and is subjected to waveform equalization, binarization, PLL, demodulation and error correction to be outputted to a memory 105. A system controller 106 performs the processing of the regenerative data from the memory 105 and the control of an optical head control means. |
