| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable stable offset compensation even in the shifted state of an objective lens. <P>SOLUTION: The optical integrated unit 60 includes a light source 65 for radiating a light toward an optical recording medium 64, a light receiving element 66 for receiving a reflected light from the optical recording medium, a first light branching means for guiding the reflected light to the light receiving element, and a second light branching means 68 disposed between the optical recording medium and the first light branching means to branch the reflected light at least into three lights including first to third lights 74, 75, and 76 in the radial direction of the optical recording medium. An MPP signal is generated from the first light passed through the first light branching means, and objective lens shifting signals are generated from the second and third lights passed through the first light branching means. A tracking error signal (TES) capable of stable offset compensation is obtained based on these signals. A stable tracking servo operation is realized by using the TES for a control signal. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
