Who said that optical data storage is becoming obsolete? According to a news published at Ars Technica, a new way to store data using optical technologies has been created by chemical researchers at University of California.
The new technique will use not only a single state to store data on a disc, like the current optical discs (CD, DVD or Blu-ray), but the entire volume of the disc, making possible to store as much as 1 TB on a standard-size (120mm x 1.2mm) optical disc.
The principle used is a bit complicated. The blank media contains a matrix with a colourless molecule embedded, named a dye precursor, which is able to react with acids. When an acid reacts with the precursor, it will create a fluorescent molecule that can be detected by a laser beam, like the land and pits of a DVD.
In the matrix there are also other molecules that can be converted into an acid with a proper laser beam. So, when the laser hits the acid precursor it will start the conversion of the dye precursor into a fluorescent dye.
By focusing properly the laser beam, it is possible to create a series of fluorescent spots that basically are the same thing of pit and lands of a standard DVD disc, but scattered on the entire matrix, and not only on a single layer.
From the article it is not fully clear if this technology can be used only for write once media or also for rewritable discs, but it seems promising anyway.