Patent ID: 6844043

Claim:
An optical disk for recording information, comprising: a resin substrate having grooves on one surface of the resin substrate; a reflection layer formed over the grooves such that the reflection layer lays over the resin substrate in accordance with a shape of the grooves; an optical characteristic change material layer formed on the reflection layer such that the optical characteristic change material layer fills in depressions defined by the respective grooves and extends over protrusions between the grooves, the optical characteristic change material layer changing optical characteristics when a light beam is radiated thereon; a protective layer formed over the optical characteristic change material layer, the protective layer being light transmissive; and a cover layer formed over the protective layer such that the reflection layer, the optical characteristic change material layer, and the protective layer are sealed on the resin substrate by the cover layer, the cover layer being light transmissive, wherein the resin substrate is harder than the cover layer at least when the optical beam is radiated on the optical characteristic change material layer in the depressions of the grooves.