| 摘要 |
<P>PROBLEM TO BE SOLVED: To appropriately perform gap control between an optical system and an optical recording medium at a distance where near field light is generated regardless of the driving speed of the optical recording medium. <P>SOLUTION: An electrostatic charge pressure source 1 is connected to a turntable 2 with an optical disk placed thereon, and the electrostatic charge pressure source 1 charges the turntable 2 and the optical disk 3 to have unipolarity. Meanwhile, in an optical head 4, an electrode 9 is provided on an end surface facing the optical disk of an SIL 11 constituting an objective lens part, and control voltage 5 is applied to the electrode 9 to thereby charge electric charge to the SIL end surface facing the optical disk 3. An electric charge amount for charging the electrode 9 is controlled by the control voltage 5 in accordance with a determination value 5 of gap length to thereby perform such gap control so as to keep the gap length 6 constant. <P>COPYRIGHT: (C)2004,JPO |
