Japan: Nano-glass film

New Glass Forum (NGF) has engineered technology for producing a thin “nano-glass“ film on the surface of an optical disk, which could ensure a huge, terabyte capacity. (One terabyte is equivalent to…

New Glass Forum (NGF) has engineered technology for producing a thin “nano-glass“ film on the surface of an optical disk, which could ensure a huge, terabyte capacity. (One terabyte is equivalent to 1,000 gigabytes.) Theoretically, this film could have a four times greater recording density. The glass film was made by depositing and sophisticating prismatic nano-particles of cobalt oxide on the surface of an optical disk. Radiation from a blue semiconductor laser increases the refraction factor by up to 40%, the highest ever achieved. The refraction factor indicates condensing power. Change to a higher refraction factor is reversible, according to the researchers involved. NGF has also discovered that another metallic glass film, composed of the three elements of cobalt, chromium and zirconium, can exhibit a condensing power more than that of cobalt oxide glass. These developments have been achieved as part of the “Nano-glass technology project” supported by NEDO (New Energy and Industrial Technology Development Organization). A thin film of the special glass deposited on an optical disk can reduce by one-fourth the cross section of the laser beam that is applied for reading and/or writing. This results from a change in the refraction factor of the glass. The 40% change in the refraction factor gives rise to a four times greater memory density. Prismatic cobalt oxide particles with a spinel structure were developed by Hitachi; R&D work on the glass was carried out at the Hitachi Room of NGF“s nano-glass Tsukuba laboratory.