Direct read after write optical disk and optical recording media

摘要

PROBLEM TO BE SOLVED: To provide a material for a write-once optical disk and an optical recording medium which can absorb a light of a wavelength in a wide area and is suitable for forming an optical disk of high density and high capacity by recording by a light of a short wavelength and, moreover, which makes it unnecessary to replace dye being used or to redesign a manufacturing process. SOLUTION: A write-once optical disk comprises a base 10, a reacting layer 20 and a reflecting layer 30 at least. The reacting layer 20 is formed on the base 10 and the reflecting layer 30 is formed on the reacting layer 20. The reacting layer 20 has a thickness exceeding 100Å and is made of a metal contact induced type crystallization semiconductor and it has high reflectance before recording and low reflectance after recording. The reflecting layer 30 is constituted of one of Al, Au, Cu, In, Ga and Sn, at least, and has a thickness exceeding 100Å.