Patent ID: 7057991
Filing Date: 2006-06-06
Classification: G11B

Abstract:
1. An apparatus detecting a defect in a radio frequency (RF) signal from an optical disc, the apparatus comprising: an average maximum value detecting unit that calculates an average maximum value of maximum values of the RF signal; an average minimum value detecting unit that calculates an average minimum value of minimum values of the RF signal; an instantaneous maximum value detecting unit that calculates a maximum value of the RF signal at an instant of time when the RF signal is input; an instantaneous minimum value detecting unit that calculates a minimum value of the RF signal at an instant of time when the RF signal is input; and a defect detecting unit that compares the average maximum value, the average minimum value, the instantaneous maximum value, and the instantaneous minimum value and generates a defect signal indicating that the RF signal is abnormal, using a predetermined peak threshold level and a predetermined bottom threshold level.