| 摘要 |
PURPOSE:To move plural optical heads on the same track at the device provided with plural optical heads. CONSTITUTION:Light in a linearly polarizing direction provided with an S polarized light component and P polarized light component is emitted from a laser diode 9 to a reflecting plane 1a of a polarized light reflection mirror 1. Optical heads A and B can be independently moved to a guide part 3. The S-polarized light component of light from the laser diode 9 is reflected by the polarized light reflection mirror 1 of the optical head B and converged to a disk 5 by an objective lens 2, and the P-polarized light component is transmitted through the polarized light reflection mirror 1, reflected by a full reflection mirror 6 of the optical head A and converged to the disk 5 by an objective lens 7. The reflected return beams from respective convergent spots are splitted into the S-polarized light component and the P-polarized light component by a polarized light beam splitter 13, and the return beams from the optical heads A and B are received by pin photodiodes 15 and 17. |
