OPTICAL DISK EVALUATION METHOD

摘要

PROBLEM TO BE SOLVED: To realize an optical disk evaluation method capable of detecting the number of defects or the number of errors actually coming into problem for the optical disk. SOLUTION: This method is arranged so that a 1st defective position detecting signal for detecting an optical disk reproducing signal by a certain threshold and a 2nd defect detecting signal obtained by expanding the defect with the plural detection unit lengths more than two before and after this defective position detecting signal are obtained, and also a 3rd defect detecting signal is obtained, which includes the plural 1st defect detecting signals including an overlapped part of the 2nd defect detecting signal as one defect signal when the defective signal exists such as overlapping the defective position of the 2nd defect detecting signal.