Patent ID: 8085630

Claim:
A disk apparatus that irradiates a laser beam on an optical disk to record and/or reproduce information, comprising: an optical detector unit that outputs an electric signal in response to a reflected beam amount from the optical disk; a servo error signal generating unit that generates a servo error signal from an output signal of the optical detector unit; a feed back control unit that generates a drive signal to drive a servo actuator in accordance with the servo error signal and perform a feed back control; a disk rotation unit that rotates the optical disk; a rotation phase detecting unit that detects a rotation phase of the disk rotation unit; an iterative learning control unit that has a suppression effect against a frequency disturbance of integer multiple of a rotation frequency; an adder unit that adds an output signal from the iterative learning control unit to a first predetermined signal on a servo loop; and a servo deviation detecting unit that detects a servo deviation by using a second predetermined signal on the servo loop to store a range, in which the servo deviation is detected, of the rotation phase as a servo deviation detected phase range, wherein a suppression degree of the iterative learning control unit increases against the frequency disturbance of integer multiple of rotation frequency, for a time period during which the rotation phase becomes within a predetermined rotation phase range including the servo deviation detected phase range.