Patent ID: 8599661

Claim:
An optical disk device comprising: an objective lens for condensing information light applied to a recording layer of an optical recording medium, the optical recording medium having said recording layer for recording information by forming a three-dimensional recording mark and a servo layer for a servo, the servo layer being disposed so as to be adjacent to the recording layer, and condensing servo light applied to said servo layer; a lens driving section configured to displace said objective lens; an information light condensing point changing mechanism for displacing a focus of said information light; a servo light condensing point changing mechanism for displacing a focus of said servo light; and a control section configured to: control said lens driving section so as to displace said objective lens to a reference lens position, the reference lens position determined based upon a recording depth at which said information light is applied; control said information light condensing point changing mechanism so as to adjust the focus of said information light to the recording depth when the objective lens is placed at said reference lens position; and control said servo light condensing point changing mechanism so as to adjust the focus of said servo light to said servo layer when the objective lens is placed at said reference lens position.