MARK LENGTH SORTING DEVICE, MARK LENGTH SORTING METHOD, MAXIMUM MARK LENGTH DETECTOR AND MAXIMUM MARK LENGTH DETECTING METHOD

摘要

PROBLEM TO BE SOLVED: To detect the maximum mark length by eliminating inappropriate mark length due to a flaw and contamination, etc., on an optical disk when the largest mark length of a signal recorded in the optical disk is detected. SOLUTION: This mark length sorting device is provided with a mark length measuring instrument 100 to measure the mark length of the signal read from the optical disk, a mark length sorting part 120 to divide one kind of mark length by the other kinds of the mark length for two kinds of continuous mark length measured by the mark length measuring instrument 100, to sort and output a part of the mark length among kinds of the mark length measured by the mark length measuring instrument 100 based on a result by comparing a division result and a prescribed threshold and a maximum length detecting part 130 to detect the maximum mark length as the maximum mark length among kinds of the mark length outputted from the mark length sorting part 120.