Optical recording medium
AssigneeKobe Steel, Ltd.
InventorsHironori Kakiuchi, Hideo Fujii, Norihiro Jiko
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Abstract
An optical recording medium of a pitting recording type, to which recording marks are formed by irradiation with a violet laser beam having a wavelength λ in the range of about 380 to about 450 nm, includes a substrate having a surface provided with guide grooves and lands, and a metal recording layer in which recording marks are formed by irradiation with a laser beam. The guide grooves and the lands meet conditions expressed by: λ/18≦DG≦λ/11 (1) 1.5≦WG/WL≦3.5 (2) Where λ is the wavelength of the laser beam used for writing and reading, DG, is the depth of the grooves, WG is the width of the grooves, and WL is the width of lands formed on the substrate, and the wavelength λ is in the range of 380 to 450 nm.
Claims2
An optical recording medium comprising:
- a substrate having a surface provided with guide grooves and lands;
- and
- a metal recording layer in which recording marks are formed by irradiation with a laser beam;
- wherein the guide grooves and the lands meet conditions expressed by:
- λ/18≦DG≦λ/11 (1)
- 1.5≦WG/WL≦3.5 (2)
- where λ is the wavelength of the laser beam used for writing and reading, DG is the depth of the grooves, WG is the width of the grooves, and WL is the width of lands formed on the substrate, and the wavelength λ is in the range of 380 to 450 nm.
Dependencies are inferred from the claim text.