A disk drive apparatus includes: head means for performing laser irradiation to and detection of reflected light from an optical disk recording medium and having a focus bias mechanism and a spherical aberration correction mechanism; focus bias means for driving the focus bias mechanism to add a focus bias to a focus servo loop; spherical aberration correction means for driving the spherical aberration correction mechanism based on a spherical aberration correction value; evaluation value creating means for creating an evaluation value based on reflected light information obtained by the head means; adjustment means for adjusting the focus bias and the spherical aberration correction value; and control means for determining whether data is written on at least one track of the tracks adjacent to an adjustment use range on the recording medium and controlling an adjustment operation on the focus bias and the spherical aberration correction value by the adjustment means based on the determination result.

 
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