High Precision Tracking Servo System for Next Generation Optical Disc System on condition of Rotational Speed 8000 rpm

In next generation optical disc system, the disc rotation speed becomes nearly equal to 10000[rpm]. Therefore, the tracking servo system for next generation optical disc system must have the high precision performance and the wide bandwidth. However, since the optical disc systems have a radial run-out, its phenomenon becomes the periodic disturbance whose bandwidth depends on the disc rotational speed. Hence, the tracking servo system of the next generation optical disc system should have the robust and high precision control against the high speed periodic disturbance whose rotational speed is nearly equal to 10000[rpm]. This paper proposes a new structure of robust tracking servo system, which suppresses the high speed periodic disturbance whose rotational speed is nearly equal to 10000[rpm]. The experiment results point out that the proposed system well regulates the high precision tracking servo control on condition of the disc rotation speed 8000[rpm], which is equal to CD system of 40 X speed.