SPHERICAL ABERRATION COMPENSATION CONTROL DEVICE AND AN OPTICAL DISK DEVICE, ESPECIALLY IN RELATION TO CONTROLLING A SPHERICAL ABERRATION COMPENSATOR WHICH COMPENSATES FOR A SPHERICAL ABERRATION OF AN OPTICAL BEAM IRRADIATING AN OPTICAL DISK

摘要

PURPOSE: A spherical aberration compensation control device and an optical disk device are provided to generate a spherical aberration control signal such that a sum of compensations corresponding to components of the control signal can be substantially zero for a target compensation, and to use the control signal when controlling a spherical aberration compensator, thereby quickly compensating for a spherical aberration. CONSTITUTION: A spherical aberration control signal generator(12) generates a spherical aberration control signal. An output portion(14) outputs the spherical aberration control signal to a spherical aberration compensator(112). Compensations in which a spherical aberration is compensated for are changed by the spherical aberration compensator(112) according to components of the spherical aberration control signal. The spherical aberration control signal generator(12) generates the spherical aberration control signal such that a sum of the compensations corresponding to each component of the control signal can be substantially zero for a target compensation.