Patent ID: 8154966
Filing Date: 2012-04-10
Classification: G11B

Abstract:
1. An information reproducing apparatus comprising: an offset adding device for adding an offset value which can be set to be variable, to a read signal read from a recording medium; a correcting device for correcting waveform distortion occurring in a read signal corresponding to at least a long mark, of the read signal to which the offset value is added by said offset adding device; and a waveform equalizing device for performing a waveform equalization process on the read signal in which the waveform distortion is corrected, wherein the offset value is set on the basis of at least one of (i) an asymmetry value which indicates a shift amount between an amplitude center of a read signal obtained by reading record data with the shortest run length of the read signal and an amplitude center of a read signal which provides a maximum amplitude of a read signal; (ii) an entire β value which indicates an average value of the amplitude center of the read signal; and (iii) a partial β value which indicates deviation between the amplitude center of the read signal obtained by reading the record data with the shortest run length of the read signal and the amplitude center of the read signal obtained by reading the record data with the second shortest run length of the read signal.