Patent ID: 7932015

Claim:
An optical recording medium comprising a substrate, a light transmission layer, and a plurality of recording layers laminated via at least intermediate layers and disposed between the light transmission layer and the substrate, the recording layers constituted so that a laser beam is projected onto the plurality of recording layers via the light transmission layer, at least one of the recording layers other than a recording layer farthest from the light transmission layer among the plurality of recording layers containing at least one element M selected from a group consisting of Ni, Cu, Si, Ti, Ge, Zr, Nb, Mo, In, Sn, W, Pb, Bi, Zn and La, at least one element selected from a group consisting of S, O, C and N as a primary component, and at least one metal different from the element M and selected from a group consisting of Mg, Al and Ti, wherein the at least one recording layers contains the at least one element selected from the group consisting of S, O, C and N and the at least one metal different from the element M and selected from the group consisting of Mg, Al and Ti in a form of a chemical compound thereof, and wherein the at least one element selected from the group consisting of S, O, C and N and the at least one element M are combined upon being irradiated with the laser beam to form a crystal of a chemical compound thereof, thereby recording information in the at least one recording layer.