Optical recording medium, information recording apparatus, and information reproducing apparatus

An optical recording medium having a plurality of recording layers of a double-spiral structure in which information is recorded on both of land tracks and groove tracks, wherein

• at least a first recording layer, a second recording layer, a third recording layer, and a fourth recording layer are provided as said recording layers,
• spirals of said first recording layer and said third recording layer are in a forward direction,
• spirals of said second recording layer and said fourth recording layer are in a backward direction,
• a first recording direction from an inner periphery toward an outer periphery of the optical recording medium and a second recording direction from the outer periphery toward the inner periphery of the optical recording medium are defined as the order of recording information,
• the recording direction of said first recording layer and said third recording layer is one of said first recording direction and said second recording direction,
• the recording direction of said second recording layer and said fourth recording layer is the other of said first recording direction and said second recording direction, and
• physical addresses are allocated in the order of one of a land track and a groove track of said first recording layer, one of a land track and a groove track of said second recording layer, the other of the land track and the groove track of said first recording layer, the other of the land track and the groove track of said second recording layer, one of a land track and a groove track of said third recording layer, one of a land track and a groove track of said fourth recording layer, the other of the land track and the groove track of said third recording layer, and the other of the land track and the groove track of said fourth recording layer.

An information recording apparatus for recording information onto an optical recording medium having at least a first recording layer and a second recording layer of a double-spiral structure in which information is recorded on both of land tracks and groove tracks, wherein

• a spiral of said first recording layer is in a forward direction,
• a spiral of said second recording layer is in a backward direction,
• a first recording direction from an inner periphery toward an outer periphery of the optical recording medium and a second recording direction from the outer periphery toward the inner periphery of the optical recording medium are defined as the order of recording information,
• information is recorded in said first recording layer in one of said first recording direction and said second recording direction,
• information is recorded in said second recording layer in the other of said first recording direction and said second recording direction, and
• physical addresses for recording are allocated in the order of one of a land track and a groove track of said first recording layer, one of a land track and a groove track of said second recording layer, the other of the land track and the groove track of said first recording layer, and the other of the land track and the groove track of said second recording layer.

An information reproducing apparatus for reproducing information from an optical recording medium having at least a first recording layer and a second recording layer of a double-spiral structure in which information is recorded on both of land tracks and groove tracks, wherein

• a spiral of said first recording layer is in a forward direction,
• a spiral of said second recording layer is in a backward direction,
• a first reproducing direction from an inner periphery toward an outer periphery of the optical recording medium and a second reproducing direction from the outer periphery toward the inner periphery of the optical recording medium are defined as the order of reproducing information,
• information is reproduced from said first recording layer in one of said first reproducing direction and said second reproducing direction,
• information is reproduced from said second recording layer in the other of said first reproducing direction and said second reproducing direction, and
• information is reproduced following physical addresses allocated in the order of one of a land track and a groove track of said first recording layer, one of a land track and a groove track of said second recording layer, the other of the land track and the groove track of said first recording layer, and the other of the land track and the groove track of said second recording layer.

An information reproducing apparatus for reproducing information from an optical recording medium having at least a first recording layer and a second recording layer of a double-spiral structure in which information is recorded on both of land tracks and groove tracks, wherein

• a spiral of said first recording layer is in a forward direction,
• a spiral of said second recording layer is in a backward direction,
• information has been recorded in said first recording layer in the direction from an inner periphery toward an outer periphery of said optical recording medium,
• information has been recorded in said second recording layer in the direction from the outer periphery toward the inner periphery of said optical recording medium,
• either of said first recording layer and said second recording layer has been divided into N zones (zone 1 to zone N) from the inner periphery toward the outer periphery of said optical recording medium,
• first information has been recorded on one of a land track and a groove track in zone n (n:
• a natural number not less than one and not more than N) of said first recording layer, and second information subsequent to said first information has been recorded on one of a land track and a groove track in zone n of said second recording layer, and
• a driving device is provided for driving a pickup so that said first information is reproduced following physical addresses, the focus of said pickup is slid by a predetermined amount in the direction toward the inner periphery of said optical recording medium with a focus jump from said first recording layer to said second recording layer, and then said second information is reproduced following physical addresses.

An information reproducing apparatus for reproducing information from an optical recording medium having at least a first recording layer and a second recording layer of a double-spiral structure in which information is recorded on both of land tracks and groove tracks, wherein

• a spiral of said first recording layer is in a forward direction,
• a spiral of said second recording layer is in a backward direction,
• information has been recorded in said first recording layer in the direction from an outer periphery toward an inner periphery of said optical recording medium,
• information has been recorded in said second recording layer in the direction from the inner periphery toward the outer periphery of said optical recording medium,
• either of said first recording layer and said second recording layer has been divided into N zones (zone 1 to zone N) from the inner periphery toward the outer periphery of said optical recording medium,
• first information has been recorded on one of a land track and a groove track in zone n (n:
• a natural number not less than one and not more than N) of said first recording layer, and second information subsequent to said first information has been recorded on one of a land track and a groove track in zone n of said second recording layer, and
• a driving device is provided for driving a pickup so that said first information is reproduced following physical addresses, the focus of said pickup is slid by a predetermined amount in the direction toward the outer periphery of said optical recording medium with a focus jump from said first recording layer to said second recording layer, and then said second information is reproduced following physical addresses.