Patent ID: 8699313
Filing Date: 2014-04-15
Classification: G11B

Abstract:
1. An optical information recording medium comprising: a light transmittable layer having an incident surface on which reproduction light is incident; two or more information recording layers; a substrate, the light transmittable layer, the information recording layers, and the substrate being stacked in this order from an incident side on which the reproduction light is incident; and an intermediate layer that separates the information recording layers from each other, the two or more information recording layers having information recorded thereon as marks and spaces by a predetermined modulation method, the two or more information recording layers each including (i) a group of pre-pits constituting the marks and the spaces and (ii) a super-resolution film, the marks and the spaces constituted by the group of pre-pits having different lengths, an average length of a smallest mark that is smallest in length among the marks constituted by the group of pre-pits and a smallest space that is smallest in length among the space constituted by the group of pre-pits being less than or equal to a resolution limit of a reproduction optical system for reproducing the information recorded on the information recording layers, the resolution film being a film that enables the reproduction optical system to reproduce information recorded by the group of pre-pits, the group of pre-pits being formed so that a push-pull signal for the reproduction optical system to reproduce the information recorded by the group of pre-pits is negative in polarity.