Patent ID: 7916593

Claim:
An optical disk device comprising: a rotational drive portion for driving an optical disk to rotate; and a controller for controlling said rotational drive portion: to drive said optical disk to rotate at a constant angular speed when a position of an emitted beam output from an optical pickup unit is in a region of the optical disk that is between a center of said optical disk and a first track, the first track being between the center and a periphery of said optical disk, and to drive said optical disk to rotate at a constant linear velocity when the position of the emitted beam output from the optical pickup unit is in a region of the optical disk that is between said first track and a track at an outer periphery of said optical disk, wherein said controller performs the functions of: performing processing for retrying to access said optical disk by the optical pickup unit when access failure occurs, judging whether or not the access failure is caused by a defect of said optical disk, judging if the access failure repeatedly occurs in a predetermined range of tracks on said optical disk, when said controller judges that access failure is caused by the defect of said optical disk when the optical pickup unit attempts to access a designated address on the optical disk, said controller performs processing for changing an access destination to an address separated from the address that caused a failed access attempt, by a distance that is equal to a width of a first address, and determining whether access to the optical disk is possible at a predetermined reference position of said optical disk and if information relating to the designated address is read by a read processor of the optical disk device, and when access is possible at said reference position, the controller changes the access destination to an address separated from the address that caused a failed access attempt, by a distance equal to a second address width, the second address width being longer than said first address width, and when access is not possible at said reference position, the controller executes a predetermined internal error processing.