Patent ID: 7304919

Claim:
An optical information reproducing apparatus for recording or reproducing information by controlling rotation of an optical disk so as to provide a constant linear velocity by changing a rotation frequency in accordance with a radial-direction position of an optical spot, said apparatus comprising: a circuit configured to control rotation of the optical disk by changing a rotation frequency thereof; a focusing servo control circuit and a tracking servo control circuit for the optical spot; and a circuit configured to adjust a servo-loop gain of a tracking servo control in accordance with the change of the disk rotation frequency, wherein said circuit configured to adjust the servo-loop gain of tracking servo control adjusts the servo-loop gain so that when a servo gain at a highest rotation frequency Wmax is represented by Gmax, and a rotation frequency is represented by Wcurr, a servo gain Gcurr satisfies the following relationship: Gcurr =Gmax ×( Wcurr/Wmax ) 2 .