Optical recording medium and its designing method

Abstract

In an optical recording medium of land/groove recording system, a sufficient tilt margin and a reduced cross talk are realized simultaneously with a sufficiently increased output. Provided is an optical recording medium having a light-transmitting substrate formed with grooves wherein the grooves and the region between adjacent grooves are used for the recording track, and a reading beam is irradiated through the light-transmitting substrate, wherein the relations: −12.6T+15.6≦x≦25T−3.8, and 0.55≦T≦0.68 are satisfied when the reading beam has a wavelength of λ, the light-transmitting substrate has a refractive index at the wavelength λ of n, the reading optical system has a numerical aperture of NA, recording track pitch is PT, the groove has a depth of λ/(x·n), and T is PT/(λ/NA).

Dependencies are inferred from the claim text.