OPTICAL STORAGE DEVICE AND CONTROL METHOD

摘要

A focusing control section focuses an objective on a predetermined portion in the radial direction of a medium when the medium is loaded, and a reference position learning section calculates an average current by measuring the current corresponding to one rotation of the medium, and stores in a memory the calculated average current as a reference current for positioning the objective at a reference position where focusing control is started. A reference position control section positions the objective at the reference position determined by the learning according to the reference current in the focusing after the learning, and the focusing control section makes focusing.