Loading patent…
AssigneeTosoh Corporation
InventorsKoyata Takahashi, Koji Katayama, Keiichiro Nishizawa
Estimating the term…
[Problem]A surface-side reproduction type optical recording medium exhibiting high reliability in continuous tests of recording and being suitable for near field recording capable of obtaining good recording/reproducing characteristics is presented. [Means for solving the problem] The surface-side reproduction type optical recording medium carries out recording or reproducing with laser beams from an optical head having a numerical aperture NA of more than 1 wherein the optical head is floated from the surface of the medium at a height of λ/4 or less where λ is the wavelength of the laser beams, said optical recording medium comprising a substrate, and at least a recording layer and a transparent protective resin layer having a refractive index np of more than the NA formed on the substrate wherein the diameter of the laser beams on the medium surface is from 1.5 μm to 30 μm.
A surface-side reproduction type optical recording medium for carrying out recording or reproducing with laser beams from an optical head having a numerical aperture NA of more than 1 wherein the optical head is floated from the surface of the medium at a height of λ/4 or less where λ is the wavelength of the laser beams, the surface-side reproduction type optical recording medium being characterized in that at least a recording layer and a transparent protective resin layer having a refractive index np of more than the NA are formed on the substrate, and the diameter of the laser beams on the medium surface is from 1.5 μm to 30 μm.
A surface-side reproduction type optical recording medium for carrying out recording or reproducing with laser beams from an optical head having a numerical aperture NA of more than 1 wherein the optical head is floated from the surface of the medium at a height of λ/4 or less where λ is the wavelength of the laser beams, the surface-side reproduction type optical recording medium being characterized in that at least a recording layer and a transparent protective resin layer having a refractive index np of more than the NA are formed on the substrate, and the transparent protective resin layer includes ultra-fine particles of inorganic material having a diameter of 0.05 μm or less.
A surface-side reproduction type optical recording medium for carrying out recording or reproducing with laser beams from an optical head having a numerical aperture NA of more than 1 wherein the optical head is floated from the surface of the medium at a height of λ/4 or less where λ is the wavelength of the laser beams, the surface-side reproduction type optical recording medium being characterized in that at least a recording layer, a dielectric layer and a transparent protective resin layer having a refractive index np of more than the NA are formed on the substrate in this order, and the refractive index nd of the dielectric layer is 2.4 or more.
A surface-side reproduction type optical recording medium for carrying out recording or reproducing with laser beams from an optical head having a numerical aperture NA of more than 1 wherein the optical head is floated from the surface of the medium at a height of λ/4 or less where λ is the wavelength of the laser beams, the surface-side reproduction type optical recording medium being characterized in that a land and a groove are formed in a substrate surface;
Dependencies are inferred from the claim text.