| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable an optical pickup device to cope with various optical information recording mediums and to detect focus/tracking error signals for realizing more stable recording/reproduction. <P>SOLUTION: This optical pickup device is provided with first and second semiconductor lasers (11, 14), a hologram element 17 which diffracts the light reflected by an optical information recording medium (9 or 12) and a plurality of light receiving elements (18 to 23). The hologram element 17 has a plurality of diffraction regions and the light receiving elements (18 to 23) are arranged along an extension line connecting light outgoing positions of the two first and second semiconductor lasers (11, 14) while being separated from the lasers (11, 14) to both sides of the lasers. The diffracted light beams of a light beam 10 having a first wavelength and the diffracted light beams of a light beam 13 having a second wavelength are converged at roughly identical positions in one side and some parts (18, 19) of the light receiving elements (18 to 23) are arranged at these positions. Then, the focus/tracking error signals are obtained by signals of the elements (18 to 23) of both sides. <P>COPYRIGHT: (C)2004,JPO |
