Patent ID: 6934233

Claim:
A waveform equalizer that equalizes a waveform of a reproduction signal obtained by reproducing marks and non-marks recorded on a recording medium, comprising: a delay element that delays a propagation of the reproduction signal; a plurality of multipliers that multiply predetermined coefficients by the reproduction signal and said delayed propagation reproduction signal; a detector that detects an asymmetry of the reproduction signal arising from physical profiles of each of the marks and the non-marks, said detector outputting a detection signal representing an amount of said asymmetry; a discriminator that outputs a discrimination signal in response to a discrimination of the marks and the non-marks; a calculator that calculates a first coefficient multiplied by the reproduction signal of the marks based on said outputted detection signal, said calculator calculating a second coefficient multiplied by the reproduction signal of the non-marks, which differs from the first coefficient; and a selector that selects one of said first coefficient and said second coefficient, based upon said outputted discriminating signal.