Patent ID: 7656766

Claim:
A servo controlling method of an optical disk apparatus, comprising: determining the order of focusing servo operations of the optical disk apparatus based on various kinds of optical disks having different light transmittance depths from the surfaces of the optical disks opposite to an object lens of an optical pickup of the optical disk apparatus when each of the optical disks is placed on a turntable of the optical disk apparatus to recording layers of the optical disks; sequentially performing the focusing servo operations on the optical disk properly placed in the optical disk apparatus according to the predetermined order by sequentially focusing a lens of an optical pickup on the optical disk and advancing the lens towards the optical disk until a normal focusing is achieved on the optical disk; determining if the normal focusing was achieved during one of the focusing servo operations; and performing a corresponding tracking servo operation on the optical disk once the normal focusing is achieved on the optical disk in the course of performing the sequential focusing servo operations, wherein the various kinds of optical disk includes a CD, a DVD, and a higher-density disk having a higher density than the DVD, the higher-density disk having a light transmittance depth of 0.1 mm regarding a recording layer, wherein each focusing servo operation has a different movable distance of the lens of the optical pickup depending upon the predetermined order to prevent the lens of the optical pickup device from colliding with the optical disk, and wherein the sequentially performing the focusing servo operations performs the sequential focusing servo operation within the corresponding movable distance according to the predetermined order.