Authenticity determination apparatus of the focus error signal, the authenticity determination program of the focus error signal, a storage medium storing the program authenticity determination of the focus error signal, the authenticity determination method of the focus error signal, the type judgment program storage medium, the storage type discrimination apparatus of the medium, the storage medium has stored a type determination program storage medium, and a type discrimination method of a storage medium

摘要

PROBLEM TO BE SOLVED: To accurately determine the kind of a disk (CD/DVD, single layer/multilayer).;SOLUTION: The objective lens of an optical pickup is raised from a position far from a disk to a position near the same at a constant speed, and a peak bottom detector detects a level (peak or bottom level) from the peak to the bottom of a focus error signal obtained by its focusing movement. A servo processing microcomputer counts the number of focus error signals having peak or bottom levels equal to/higher than a predetermined minimum level among peak and bottom levels obtained during the movement of a focus on the recording layer of a disk, and determines the type of a disk 1 based on the count value. Thus, the disk type is accurately determined without being influenced by a characteristic difference between devices, variance in disk reflectance, a change in environmental temperature or false pulses generated by a wavy reproduction output.;COPYRIGHT: (C)2005,JPO&NCIPI