| 摘要 |
PROBLEM TO BE SOLVED: To provide an aberration detecting device capable of properly performing the recording and regeneration of the information which respect to an optical magnetic disc by precisely detecting and properly correcting a spherical aberration caused in a condensing optical system, and an optical pickup device having this aberration detecting device. SOLUTION: A light detecting device 7 for detecting the optical beam passed through a condensing optical system 10 comprises light detectors 7a, 7b for forming the condensing spot P1 of a first optical beam closer to an optical axis OA and light detectors 7c, 7d for forming the condensing spot P2 of a second optical beam on the outer side from the first optical beam. The spherical aberration of the condensing optical system 10 is detected on the basis of the detection signals of the detectors 7a-7d. |
