A disk drive apparatus includes: an optical pickup irradiating a laser beam onto an optical disk having one or more recording layers through an objective lens and receiving the laser beam reflected from the optical disk; a driving unit moving the objective lens in an optical axial direction of the laser beam to the optical disk in accordance with a driving signal; an interlayer distance measuring unit measuring interlayer distances of a plurality of recording layers of the optical disk; and a spherical aberration correcting unit obtaining a spherical aberration correction value for correcting a spherical aberration due to the objective lens to one of the recording layers of the optical disk. A spherical aberration correction value to another one of the recording layers is obtained on the basis of the measured interlayer distances and the obtained spherical aberration correction value to the one recording layer.

 
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> Method and apparatus for making master optical disk

> Optical information recording medium

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