Patent ID: 6693873
Filing Date: 2004-02-17
Classification: G11B

Abstract:
An information recording medium comprising:a substrate having a microscopic pattern, which includes a shape of continuous substance of approximately parallel grooves formed with a convex shaped section and a concave shaped section alternating on a surface of the substrate; a recording layer formed on the microscopic pattern; and a light transmitting layer having thickness of 0.05 mm to 0.12 mm formed on the recording layer, the microscopic pattern satisfies a relation of P&lE;&lgr;/NA, wherein P is a pitch of the convex shaped section, &lgr; is a wavelength of a reproducing light beam and NA is a numerical aperture of an objective lens; and further wherein the microscopic pattern includes modulated address information formed on both side walls of the convex shaped section viewed from the light transmitting layer as a wobble having a same period and phase on both side walls.