Optical recording medium
AssigneeSony Corporation
InventorsMasaki Kagawa, Ayumi Konishi
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AssigneeSony Corporation
InventorsMasaki Kagawa, Ayumi Konishi
Estimating the term…
An optical recording medium includes recording tracks located adjacently to each other and is provided on and/or from which information is recorded and/or reproduced by irradiating with a beam a predetermined track of those recording tracks. The track pitch between the adjacent recording tracks is adjusted so that the track pitch is made substantially equal to a distance between an intensity center of a beam spot on a laser beam irradiated plane of the medium and a location of an initial minimum intensity. By irradiating with a beam the predetermined track, therefore, the beam intensity is located around the center of the recording track that is adjacent to the minimum portion. This location results in reducing a crosstalk amount from the adjacent recording track to a minimum, thereby suppressing the loss of the crosstalk characteristic to a minimum. This makes it possible to enhance the recording density in the alignment direction of the recording tracks if an A/W in the optical system is 1.0 or lower, in which A denotes an effective radius of an objective lens in the alignment direction of the recording tracks and W denotes a beam spot size on the objective lens in the alignment direction of the recording tracks.
An optical recording medium on which information is recorded and/or from which information is reproduced by irradiating with a beam a predetermined one of recording tracks located adjacently to each other, characterized in that a track pitch between said recording tracks is made substantially equal to a distance from a center of an intensity of a beam spot on a light-applied plane of said medium to a location of an initial minimum intensity in the radial direction of the beam spot.
Dependencies are inferred from the claim text.