Optical recording medium

Abstract

A recordable optical recording medium comprising a recording layer containing an organic dye which can absorb a laser beam and a metal reflective layer directly or via another layer on a transparent supporting substrate having a pre-groove and a pre-pit, wherein the organic dye has a refractive index nk of 2.2 or more at a reproduction wavelength λ2; in relation to the reproduction wavelength λ2, the depths of the pre-groove and the pre-pit on the substrates are more than λ2/4; and the following equations are satisfied: 0.25r≦wg≦0.38r; 0.25≦wp/wg≦0.75; θgr≦θpr; and θpr≦θpt wherein r is a recording laser beam diameter represented by λ1/NA where λ1 is a recording wavelength [μm] and NA is a numerical aperture for an object lens; wg [μm] and θgr are a half value width and a cross-section tilting angle in a substrate radial direction for the pre-groove, respectively; and wp [μm], θpr and θpt are a half value width, a cross-section tilting angle in a substrate radial direction and a cross-section tilting angle in a tangential direction for the pre-pit, respectively.

Dependencies are inferred from the claim text.