Optical disk and method of magnetically separating tracks of the optical disk

An optical disk, comprising:

• a disk-shaped substrate with pits and grooves formed by emboss processing, in which a predetermined region ranging in a radial direction is used as a data region for recording/reproducing data;
• and
• at least a first dielectric layer, a magnetic layer, and a second dielectric layer that are formed on the substrate,
• wherein the data region includes a plurality of recording/reproducing tracks ranging from an innermost track to an outermost track, and is divided into a plurality of segments in a tangential direction, each segment including a pit region and a groove region;
• the pit region is provided with at least a pair of wobble pits to be used for sample servo;
• the groove region is provided with the recording/reproducing track;
• the recording/reproducing tracks are composed of the grooves;
• magnetic anisotropy of the magnetic layer positioned on each of lands between the respective recording/reproducing tracks is reduced to a level lower than that of magnetic anisotropy of the magnetic layers positioned on the grooves, so that the recording/reproducing tracks are magnetically separated, and
• magnetic anisotropy of the magnetic layers positioned on a land portion on the inner side of the innermost recording/reproducing track and a land portion on the outer side of the outermost recording/reproducing track, respectively, is reduced to a level lower than that of magnetic anisotropy of the magnetic layers positioned on the recording/reproducing tracks, so that magnetic separation is achieved on the inner side of the innermost track and the outer side of the outermost track.

An optical disk, comprising:

• a disk-shaped substrate with pits and grooves formed by emboss processing, in which a predetermined region ranging in a radial direction is used as a data region for recording/reproducing data;
• and
• at least a first dielectric layer, a magnetic layer, and a second dielectric layer that are formed on the substrate,
• wherein the data region includes a plurality of recording/reproducing tracks ranging from an innermost track to an outermost track, and is divided into a plurality of segments in a tangential direction, each segment including a pit region and a groove region;
• the pit region is provided with at least a pair of wobble pits to be used for sample servo;
• the groove region is provided with the recording/reproducing track;
• the recording/reproducing tracks are composed of the grooves;
• magnetic anisotropy of the magnetic layer positioned on each of lands between the respective recording/reproducing tracks is reduced to a level lower than that of magnetic anisotropy of the magnetic layers positioned on the grooves, so that the recording/reproducing tracks are magnetically separated;
• and
• also in the pit region, magnetic anisotropy of the magnetic layer positioned on an extension of the land is reduced to a level lower than that of magnetic anisotropy of the magnetic layer positioned on an extension of the groove.

An optical disk, comprising:

• a disk-shaped substrate with pits and grooves formed by emboss processing, in which a predetermined region ranging in a radial direction is used as a data region for recording/reproducing data;
• and
• at least a first dielectric layer, a magnetic layer, and a second dielectric layer that are formed on the substrate,
• wherein the data region includes a plurality of recording/reproducing tracks ranging from an innermost track to an outermost track, and is divided into a plurality of segments in a tangential direction, each segment including a pit region and a groove region;
• the pit region is provided with at least a pair of wobble pits to be used for sample servo;
• the groove region is provided with the recording/reproducing track;
• the recording/reproducing tracks are composed of the grooves;
• magnetic anisotropy of the magnetic layer positioned on each of lands between the respective recording/reproducing tracks is reduced to a level lower than that of magnetic anisotropy of the magnetic layers positioned on the grooves, so that the recording/reproducing tracks are magnetically separated;
• and
• the grooves are composed of a discontinuous series of grooves in the form of a spiral that is interrupted in the pit regions at an interval of not more than 7 μm.