Patent ID: 7196997

Claim:
A waveform equalizer ( 6 ) for obtaining a corrected signal S′ by performing a waveform equalization to a read signal S read out from an information carrier ( 1 ), comprising: a first filter ( 61 ) able to perform a filtering process to said read signal S; amplitude limiting means ( 62 ) able to obtain an amplitude limited read signal S LIM by limiting an amplitude level of said read signal S by a predetermined amplitude limitation value; a second filter ( 63 ) able to perform a filtering process to said amplitude limited read signal S LIM ; an adder ( 64 ) able to add the signals obtained by performing the filtering process by each of said first ( 61 ) and second filters ( 63 ), able to generate an addition result as said corrected signal S′, characterized in that a signal frequency response of said waveform equalizer ( 6 ) to signals having an amplitude smaller than said predetermined amplitude limitation value, has a notch in a first frequency region from zero to a frequency at which the signal frequency response is at a maximum amplitude.