CONTROL DEVICE AND OPTICAL DISC DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a control device for focal control or tracking control for an optical disc which operates in sampling frequency lower than a conventional one and has performance equivalent to the conventional one. SOLUTION: The control device performs the focal control or the tracking control for the optical disc by sampling control in a designated sampling frequency. The device is designed through steps of: a transfer function for a controlled object side is digitized by zero-order hold with an arbitrary sampling period (S4); the transfer function for the controlled object in a virtual region is obtained by bilinear transformation of the digitized transfer function (S6); a phase compensation element in the virtual region is obtained by a design method for a continuous time control system from the obtained transfer function (S8); and the obtained phase compensation element is transformed by the bilinear transformation to obtain the phase compensation element for the sampling control system (S10). The sampling frequency is configured to be lower than 44.1 kHz. COPYRIGHT: (C)2006,JPO&NCIPI