| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical head device miniaturized more than a conventional one. <P>SOLUTION: The optical head device 10 is provided with two types of laser light source devices 21 and 22 for recording and reproducing two types of 2-layer disks, a common signal detection light receiving element 25 for receiving laser light emitted from the two types of laser light source devices 21 and 22, an optical system 30 constituting a going path on which the laser light emitted from the laser light source devices 21 and 22 goes toward the 2-layer disks and a return path on which laser light reflected on the two-layer disks goes toward the signal detection light receiving element 25, and a driving member 50 for driving the sensor lens 42 of the optical system 30 constituting the return path to vary the optical magnification of the return path of the laser light in the signal detection light receiving element 25. <P>COPYRIGHT: (C)2009,JPO&INPIT |
