Playback signal evaluation method, information recording and reproducing method, and information recording and reproducing apparatus

摘要

PROBLEM TO BE SOLVED: To provide reproduced signal evaluating means for securing compatibility in an optical phase multivalue recording and reproduction system, and to provide decoding means whose circuit scale is suppressed.;SOLUTION: The phase of light is modulated by user data, and the phase information thereof is recorded on a recording medium. The phase information recorded on the recording medium is optically reproduced, the recorded phase information is converted into an electric signal, and the signal is adaptively equalized to be subjected to PRML decoding. A deviation in a time axis direction from a target waveform of a designated pattern is detected from the reproduced phase information to calculate a statistical average. In addition, a value of the phase reproduced from the designated pattern is extracted from the reproduced phase information to calculate a statistical average.;COPYRIGHT: (C)2012,JPO&INPIT