| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical pickup device which is capable of preventing the occurrence of noise due to return lights to a semiconductor laser at the time of recording and reproducing and erasing information with respect to an optical disk and which uses a hologram. SOLUTION: In this optical disk device, a luminous flux outgoing from a semiconductor laser 1 is made incident on an objective lens 7 with a hologram 4 to be converged on an optical disk 8 by the objective lens 7 and a reflected luminous flux from the disk 8 is made incident on the hologram 4 with the objective lens 7 to be diffracted by the holgram 4 and the reflected flux is guided a photodiode 9. In this case, an optical isolator 6 deflecting the reflected luminous flux from the disk 8 is provided between the semiconductor laser 1 and the objective lens 7. |
