| 摘要 |
PROBLEM TO BE SOLVED: To quickly read TOC information in disk loading without using a limit switch. SOLUTION: From an optical disk 10 rotationally driven by a motor 11 so as to become a constant linear velocity at a TOC position of the optical disk 10, recorded EFM signals are read by an optical pickup head 12 and are amplified with amplifier 13, and then are send to a signal processing circuit 20, where an inverted frequency value is detected. The detected inverted frequency value is sent to a calculation function section 41 of a control circuit 40, where it is compared with the inverted frequency value of a reference EFM signal, so that the present position of the optical pickup head 12 in the radial direction of the disk is determined. The amount of head transport is determined from the determined position in the radial direction of the disk and the TOC position, and the optical pickup head 12 is transported by the amount in the radial direction of the disk to access the TOC access. COPYRIGHT: (C)2004,JPO&NCIPI
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