Optical disk device using a new alternate list for defect correction

摘要

The optical disk device according to the present invention has a data reader which reads data of an optical disk, the disk being provided in advance with an alternate area that serves as a substitute for a defective data area when there is a defect in a data area. The disk is recorded in advance with list information consisting of a plurality of sets each of the sets comprising a position on the disk for the data area and an address of the alternate area. The optical disk also includes buffers for buffering a data area that is defective after correcting it, and a storage device for storing a new alternate list on which is recorded the correspondence relationship between the alternate area and its buffer destination.