| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical recording medium which individually and additionally records a large volume of additional information which has low visibility with a simple device in addition to reproduction-only main information formed of recesses and protrusions, and also to provide a manufacturing method of the optical recording medium. <P>SOLUTION: By providing an additional information recording layer having a first metal thin film which has Al as a principal component and a second metal thin film which has Ni as a principal component on a substrate where the main information is recorded by forming the recesses and protrusions on a surface, the large volume of additional information is recorded without destroying the main information even when the additional information is recorded by being superimposed on the reproduction-only main information formed of the recesses and protrusions by radiating a laser pulse to partially spread a material of two types of metal thin films in a film thickness direction. By recording the additional information by being superimposed on the main information, the additional information is made less visible, and additional recording with high security is enabled. <P>COPYRIGHT: (C)2011,JPO&INPIT |
