An information recording medium includes a substrate having a microscopic
pattern which has a shape of continous 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 that is
formed on the microscopic pattern and a light transmitting layer having
thickness of 0.05 mm. to 0.12 mm. that is formed on the recording layer.
The microscopic pattern is formed so as to satisfy a relation of
P.ltoreq..gamma./NA, wherein P is a pitch of the convex shaped section or
the concave shaped section, .gamma. is a wavelength of reproducing light
beam and NA is a numerical aperture of an objective lens. Further, the
microscopic pattern has modulated address information formed on both side
walls of the convex shaped section that is viewed from the light
transmitting layer side as a wobble having same period and phase.
Furthermore, even when a laser beam is irradiated on the side opposite to
the substrate of the information recording medium, a reproduced signal in
high output and high quality can be obtained and an address and recorded
information can be read out accurately.
