| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an apparatus that performs position control of a beam by servo on a hologram recording and playback medium and performs recording and playback is less apt to be affected by the temperature. <P>SOLUTION: An image formed by reproduced light generated according to the form of a hologram is received by a detector 54 for servo by using a condenser lens 28. A tangential error signal and a radial error signal are generated corresponding to the position of the image on the detector 54 for servo, a movable mirror and a piezo element 60 for tracking are controlled, by using the signals and servo operation performed by the same laser light source 10 that is used for recording and playback. <P>COPYRIGHT: (C)2008,JPO&INPIT |
