Information Recording Layer of Optical Disc, Optical Disc and Disc Device

摘要

An optical disk includes a substrate covered with an information recording layer. The information recording layer includes a recording material and an exothermic material dispersed in the recording material. The exothermic material absorbs recording light for recording information, and then generates heat. An external dimension of the exothermic material is smaller than the diffraction limit of reading light for reading information. The recording material has absorptance of a wavelength of the recording light lower than that of the exothermic material. Information is recorded on the recording material as the light refraction index of the recording material changes due to heating.