Optical recording medium, master disc for manufacturing optical recording medium, and device and method for manufacturing master disc for manufacturing optical recording medium

A master for manufacturing optical recording medium where a groove and plural pits formed and arranged dispersedly in a circumference direction, are formed on a substrate,

• wherein the groove of the optical recording medium is formed to have a U-shaped cross section which is shallower than a depth of the pits.

A method of manufacturing a master for manufacturing optical recording medium where a groove and plural pits formed and arranged dispersedly in a circumference direction, are formed on a substrate,

• wherein a single exposure beam supplied from a light source is divided into two beams with a first beam splitter, one beam of the divided beams is pit-modulated and irradiated to a surface of the master to form a latent image for forming the pits, the other beam of the divided beams is optically deflected for wobbling, and divided into plural exposure beams with a second beam splitter, and the plural exposure beams are arranged to be aligned at certain widths in the radius direction of the master with a polarization beam splitter and an exposure beam with a spot wider in the radius direction of the master than that of the single exposure beam is irradiated to the surface of the master in order to form a latent image for forming the groove with an U-shaped cross section on the surface of the master.

A method for manufacturing a master for manufacturing optical recording medium having at least a groove on a substrate,

• wherein a single exposure beam supplied from a light source is optically deflected for wobbling and divided into plural exposure beams with a beam splitter, the plural exposure beams are arranged to be aligned at certain widths in the radius direction of the master with a polarization beam splitter, and an exposure beam with a spot wider in the radius direction of the master than that of the above single exposure beam is irradiated to a surface of the master in order to form a latent image for forming the groove with an U-shaped cross section on the surface of the master.