Hitachi Etches Data on Glass to Live Forever

Hitachi’s data density is 40MB per square inch, slightly exceeding a CD’s storage density of about 35MB per square inch.

Forget racks of spinning disk arrays. And tape as a storage medium? So very ancient. No, Hitachi believes that future generations of mission-critical storage will run on etched glass—allowing data to essentially live forever.

In a translated press release, Hitachi concluded that etching data within quartz glass could store it for millions of years. Hitachi’s research was conducted in conjunction with Prof. Kiyotaka Miura of Kyoto University.

The data density is 40MB per square inch, slightly exceeding a CD’s storage density of about 35MB per square inch. Hitachi used a laser to melt dots into the surface of the quartz glass, creating an optical image roughly similar to a QR code. The 40 MB/sq. in density was achieved using four-layer recording. According to the AFP, the test “chip” of glass measured two centimeters (0.8 inches) square and two millimeters (0.08 inches) thick.

The glass was stress-tested on the order of 1,000 degrees centigrade for about 2 hours, which corresponds to a retention period of a few hundred million years. That’s probably good enough for even Amazon’s Glacier, which relies on tape technology that (at least for the moment) remains faster and cheaper than quartz glass. But the latter wins in the resiliency category, given how it’s the same material used in test tubes and flasks to hold acids and other caustic chemicals.

Hitachi told AFP it had developed a technique to read data back from the glass using an optical microscope. Since focusing the microscope on one layer blurs the others, Hitachi developed a technique to filter out the “noise” of the other layers with 15 dB accuracy—enough to achieve data reads without any errors.

Hitachi added that it hopes to achieve a recording density that will make the technology good enough for practical applications.

Obviously, Hitachi is talking about read-only archival storage, which is used by government agencies, museums and other organizations. A full enterprise archive or disaster recovery system usually relies on a combination of redundant storage systems, offsite backup, and even WORM options to meet compliance. At least in theory, though, it’s possible that the Hitachi glass technique could become the foundation of the digital equivalent of the Corbis photo vault, where famous photos such as “Albert Einstein Sticking Out His Tongue” and “Marilyn Monroe Having Skirt Trouble on a Subway Grate” are stored at zero degrees Fahrenheit.

Other startups have pitched new forms of archival media, including the Millenniata M-Disc, which uses a rock-like layer of material upon which to read and write data. Talk about setting things in stone.


Image: Hitachi