| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup device capable of performing reading operation of signals recorded on optical disks with different standards by three laser beams with different wavelengths. <P>SOLUTION: A photodetector is provided in which laser beams emitted from a three-wavelength laser diode are collected on signal recording layers provided to a first optical disk, a second optical disk, and a third optical disk, and a first light receiving unit 12a for receiving return light of a first laser beam, a second light receiving unit 12b for receiving return light of a second laser beam, and a third light receiving unit 12c for receiving return light of a third laser beam, the laser beams being from the respective signal recording layers, are provided in one body. The second light receiving unit 12b and the third light receiving unit 12c are composed of four division sensors with four parts, and the first light receiving unit 12a is composed of six or more sensors with three or more parts. <P>COPYRIGHT: (C)2012,JPO&INPIT |
