OPTICAL DISK, RECORDING DEVICE FOR OPTICAL DISK, METHOD FOR RECORDING IN OPTICAL DISK, PLAYING BACK DEVICE FOR OPTICAL DISK, AND METHOD FOR PLAYING BACK OPTICAL DISK

摘要

PROBLEM TO BE SOLVED: To provide an optical disk, a recording device for optical disk, a method for recording in an optical disk, a playing back device for an optical disk and a method for playing back an optical disk such that the efficiency of formatting can be improved without decreasing the reliability for operation. SOLUTION: The optical disk is a rewritable optical disk having such signal recording tracks that the tracks are divided into a plurality of zones in the radial direction while one circle of the track is divided into an integer number of sectors each having a header region and a data region and that information is recorded and reproduced at a constant number of revolution in each zone but different numbers of revolution among the zones. In the header region of one sector in the integer number of sectors constituting one circle of the signal recording track, information is recorded by the method of forming recesses and projections (prepits) on the surface of the optical disk, while in the head regions of other sectors, information can be recorded by the same method (of forming phase change marks) as the method for the data regions.