| 摘要 |
PROBLEM TO BE SOLVED: To propose an optical pickup which can compensate relative tilt between an optical disk and an objective lens with sufficient precision, and an optical disk device mounted with the optical pickup. SOLUTION: This optical disk device is provided with a laser beam source 11; a grating 12 as a light flux division means which divides a light flux emitted from the laser beam source 11 into a main light flux, a first sub-light flux, and a second sub-light flux which is in approximately symmetric relation with the first sub-light flux across the main light flux; the objective lens 5 which focuses the main light flux and sub-light flux on a recording surface of the optical disk 20, respectively; a 4-divided photodetector 9-1 which is a first sub-light flux focus detection means for detecting the focus of the first sub-light flux; a 4-divided photodetector 9-2 which is a second sub-light flux focus detection means for detecting the focus of the second sub-light flux, and an operation amplifier 10 which is a tilt calculation means for calculating the relative tilt between the optical disk 20 and the objective lens 5 from the difference of detection results of the 4-divided photodetectors 9-1, 9-2. COPYRIGHT: (C)2007,JPO&INPIT
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