OPTICAL DISK DEVICE AND SEMICONDUCTOR DEVICE

An optical disk device is provided in which stable operation is realized even when an offset amount of a signal to be used for servo control changes due to environmental variations. The optical disk device generates a signal for servo control based on signals corresponding to a reflected light of a laser light irradiated to an optical disk, and detects an offset superimposed on a signal for the servo control. The optical disk device compensates the amount of the adjusted offset which has been set up so as to reduce the offset amount in initial setting for light detection corresponding to an optical disk loaded, according to the amount of change of the offset amount detected, adjusts the signal to be used for the servo control based on the amount of the offset control after the compensation, and performs the servo control based on the adjusted signal.