optical memory medium

Abstract

Abstract PURPOSE:To obtain an optical memory medium which permits rewriting and reading out with high efficiency when a laser light beam is made incident to a photomagnetic film by forming the photomagnetic film which is made substantially thick to increase the effect of Krr rotation, a thin transparent material film and an extremely thin metallic film in this order on a base. CONSTITUTION:A photomagnetic film 22 consisting of, for example, Tb23Fe77 is formed to about 600Angstrom thickness on a transparent base body 1 consisting of glass, etc. and thereafter a thin transparent SiO2 film 23 and an extremely thin metallic film 24 of extremely thin Al, etc. are formed thereon. An optical memory medium which permits recording, reproducing and erasing of information when a laser light beam 6 is made incident thereto from the film 24 side is thus obtd. An equally good result is also obtd. by forming the film 32, the film 33 and the film 34 in this order on the base plate 1 and making the beam 6 of laser light 4 incident thereto from the plate 1 side. The films 22, 34 are thus made thick and the Kerr rotating angle is increased by the interfering effect of the films 23, 33 and the films 24, 32 to prevent oxidation deterioration of the films 22, 34, by which the optical memory medium having a long life and excellent recording and reproducing efficiency is obtd.

Inventors

• 👤 Shuzo Fukunishi
• 👤 福西　修三
• 👤 Masami Miyagi
• 👤 宮城　雅美
• 👤 Norihiro Funakoshi
• 👤 宣博 舩越

Bibliographic Details