Patent ID: 6226243
Filing Date: 2001-05-01
Classification: G11B

Abstract:
An optical disk producing device including a mother disk and a ROM disk, said mother disk made by electroforming processing and a stamper produced from the mother disk, said ROM disk produced by using the stamper, the mother disk made by switching a signal level of a modulation signal at a period equivalent to an integer multiple of a predetermined fundamental period according to data to be recorded, conducting on-off control on a laser beam by using said modulation signal, comprising:edge position correction means including a correction value table;modulation signal generating means for generating a modulation signal obtained from said edge position correction means; andcorrection value table generating means comprising a signal reproducing means for reproducing data from the ROM disk, a jitter detecting means for detecting each jitter value corresponding to the combination of the pit length and the pit interval length, said each jitter value detected from said ROM disk, and a calculation means for calculating the correction value corresponding to the combination of each pit length and each pit interval length;wherein said edge position correction means further includes signal delaying means for delaying the modulation signal, the delaying time being determined with the modulation signal and a value stored in the correction value table; and furtherwherein said correction value table generating means corrects the timing of said modulation signal such that a binary signal changes while taking said predetermined fundamental period as a unit when said reproduced data from said ROM disk is converted to said binary signal using a predetermined slice level.