Patent ID: 6044052
Filing Date: 2000-03-28
Classification: G11B

Abstract:
In an apparatus for data recovery from rotating data storage disks of varying physical qualities, the apparatus having a transducer for reading a disk by irradiating the same with a beam of light, a tracking servo for holding the beam spot in alignment with a data track on the disk surface, and a focusing servo for holding the beam focused on the disk surface, a method comprising the steps of:(a) rotating a data storage disk at a first predetermined speed, with both tracking servo and focusing servo in operation;(b) recovering data from preselected part of the data track on the rotating disk;(c) ascertaining whether there are more than a predetermined number of read errors occurring during a predetermined period of time;(d) reading the disk at a second predetermined speed, which is less than the first predetermined speed, if more than the predetermined number of read errors are found to have occurred at step (c); and(e) reading the disk at a third predetermined speed, which is not less than the first predetermined speed, if more than the predetermined number of read errors are found to have not occurred at step (c).