Patent ID: 7746748
Filing Date: 2010-06-29
Classification: G11B

Abstract:
1. An optical disc device concentrating a laser beam of predetermined power on a recording surface of an optical disc, and reproducing information recorded on the optical disc based on laser beam light reflected from the recording surface of the optical disc, comprising: a light source driver generating a drive signal by superimposing a high-frequency signal onto a DC current, and applying the drive signal to a laser beam light source, thereby driving the light source; and a servo controller generating a servo signal at a signal level corresponding to a defocus amount of the laser beam relative to the surface of the optical disc based on laser beam light reflected from the recording surface of the optical disc, extracting a low-frequency component of the servo signal, and thereby controlling the frequency of the high-frequency signal to be superimposed onto the DC current in the light source driver based on the low-frequency component of the servo signal.