| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical disk device recording/reproducing information in a high-density and large-capacity optical disk by achieving spherical aberration control having a large spherical aberration correction range and high responsiveness even when the NA of an objective lens is set larger (e.g., 0.8 or more) than a conventional NA. <P>SOLUTION: This optical disk device is provided with a test signal generating means for applying a test signal to a driving means, a second amplitude detecting means for detecting the amplitude of the detected signal of a converged state detecting means, and a converged state detection correction learning means for obtaining, when the test signal is applied to the driving means by the test signal generating means, an added gain of the converged state signal correcting means so that an effective value of the converged state detected signal is minimum by the amplitude detecting means. <P>COPYRIGHT: (C)2008,JPO&INPIT |
