초록 ▼

An optical disk and its recording and playback method. The optical disk has a groove portion and a land portion, in which the land portion is at a distance of greater than or equal to 100 nm from the groove portion and the land portion has a land width greater than a groove width of the groove porti

An optical disk and its recording and playback method. The optical disk has a groove portion and a land portion, in which the land portion is at a distance of greater than or equal to 100 nm from the groove portion and the land portion has a land width greater than a groove width of the groove portion. The method includes recording the data on a groove portion and a land portion of the optical disk; and playing back the recorded data with a land reflectivity equal to groove reflectivity when the land portion is at a distance of greater than or equal to 100 nm from the groove portion and a land width of the land portion is greater than a groove width of the groove portion.

대표청구항 ▼

[ What is claimed is:] [1.] An optical disk to store data according to a land-groove recording method in which data is stored on both lands and grooves, comprising:a disk substrate to transmit an incident laser beam having an associated wavelength .lambda. which is less than or equal to 680 nm there

[ What is claimed is:] [1.] An optical disk to store data according to a land-groove recording method in which data is stored on both lands and grooves, comprising:a disk substrate to transmit an incident laser beam having an associated wavelength .lambda. which is less than or equal to 680 nm therethrough;a groove portion formed on said disk substrate and having an associated groove width, said groove portion having a groove depth d which is greater than 100 nm and which relates to the incident laser beam such that d=.lambda./(4n) with n corresponding to the refractive index of said disk substrate; anda land portion formed on said disk substrate such that said land portion is farther away from the incident laser beam than said groove portion, and said land portion having a land width greater than the groove width,wherein a distance from a center of said groove portion to a center of said land portion horizontally across said disk substrate is defined as a track pitch, and said track pitch is less than or equal to 0.7 .mu.m, such that the reflectivity of said land portion nearly equals the reflectivity of said groove portion.