An asymmetric error correction device includes an analog-to-digital (A/D)
converter sampling analog radio frequency (RF) signals reproduced from an
optical disc with a sampling period, converting the same into the digital
sampling signals, and outputting the same; a signal detector for
detecting 4T sampling signals varying in polarity thereof every four
times the sampling period among the digital sampling signals; an operator
selecting and adding a signal among the 4T sampling signals to operate an
asymmetric error value; a counter cumulatively counting the asymmetric
error value operated in the operator; and a corrector correcting a signal
level of the digital sampling signal outputted from the A/D converter if
the counted value counted by the counter is out of a predetermined
critical range. The asymmetric error is precisely corrected even in a
signal part in which the asymmetric error is minutely generated.