| 摘要 |
PROBLEM TO BE SOLVED: To compensate for aberration by detecting individual aberration due to each aberration cause. SOLUTION: A laser light is converged by an objective lens 6, projected to a magneto-optical disk 1 and reflected. The reflected light is polarized into P and S waves by a phase beam splitter 9, the P wave is fed to a push-pull tracking control unit 90, and the S wave is fed to an aberration compensating unit 10. The aberration compensating unit 10 includes a photodetector 11, a tracking control unit 12, a thickness/focusing control unit 13 and a tilting control unit 14. The photodetector 11 receives the S wave, and computes and outputs a control signal to be fed to each control unit. Signals are respectively outputted from the tracking control unit 12, the thickness/focusing control unit 13 and the tilting control unit 14, thereby the objective lens 6 is moved such that respective control signals become zero. |
