| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a disk unit which enables tilt control by tilting an objective lens for obtaining the tilting of the objective lens without increasing the parts count. <P>SOLUTION: Tilting of an objective lens 21 is obtained from a light receiving result of reflected light by making a part of light contained in a laser beam (optical beam) 11 from a laser source 1 (light emitting means) reflected by a reflecting section of the objective lens 21 (condensing means). Tilting of a disk D is obtained from the light receiving result of the reflected light from the disk D by entering a part of the light of the laser beam 11 to the disk D in a state parallel to an optical axis of the laser beam 11. Relative tilting of the objective lens 21 and the disk D is obtained from tilting obtained individually and tilting control is performed by tilting objective lens 21 based on the obtained relative tilting so that the incident light to the disk D which is a part of the laser beam 11 condensed by a condensing section of the objective lens 21 enters the disk D almost perpendicularly. <P>COPYRIGHT: (C)2007,JPO&INPIT |
