Patent ID: 7123559
Filing Date: 2006-10-17
Classification: G11B

Abstract:
1. An optical recording and/or reproducing apparatus which records and/or reproduces data from an optical disc which includes recording layers, each layer having lead-in, user data and lead-out areas, wherein each of the lead-in, user data and lead-out areas includes a groove and a land formed thereon and wobbles in the lead-in area, the user data area, and the lead-out area are modulated by different modulation techniques, the apparatus comprising: a laser diode which radiates light; a collimating lens which collimates the light radiated from the laser diode; a polarizing beam splitter which changes a path of the light according to a polarization direction of the light; an objective lens which focuses the light onto the optical disc; and a photodetector which receives the light uniformly irradiated and reflected from the lead-in, user and lead-out areas having the groove and the land formed thereon.