Patent ID: 7310292
Filing Date: 2007-12-18
Classification: G11B,H03H

Abstract:
1. An optical disk reproducing device comprising: a channel rate process data demodulation part operable to demodulate digital data from an optical recording medium on which the data is digitally recorded in a form of recording codes having a restriction that at least three of a same bit continue, by employing a channel bit frequency; a half rate process data demodulation part operable to demodulate the digital data from the optical recording medium by employing a frequency that is half of the channel bit frequency; and a process rate switching part operable to switch between the channel rate process data demodulation part and the half rate process data demodulation part, thereby switching a process rate of data demodulation, wherein the process rate switching part includes a retrial information detection part operable to detect retrial process information which indicates a re-reading process for a part where demodulation of data from the optical recording medium has failed, and judge whether or not a retrial process occurs, and the process rate switching part is operable to generate a process rate switching signal so that the half rate process data demodulation part is selected in a normal reproduction state, and the channel rate process data demodulation part is selected when the retrial information detection part judges that the retrial process occurs.