| 摘要 |
PROBLEM TO BE SOLVED: To properly control focal spot positions of numerous laser beams. SOLUTION: A servo circuit 15a generates focus error signals FE1 based on the signals received from a photodetector 14a. The servo circuit 15a impresses the generated focus error signals FE1 to a movable part 11a through a semiconductor substrate. The movable part 11a generates deformation through the impression of the focus error signals FE1 and moves the position connected with the semiconductor substrate. Similarly, a servo circuit 15b generates focus error signals FE4 based on the signals received from a photodetector 14d, impressing the focus error signals FE4 to a movable part 11b through the semiconductor substrate. The movable part 11b generates deformation through the impression of the focus error signals FE4, moving the position connected with the semiconductor substrate. |
