TDK plans 10-layer, 320GB optical disc

Optical media is perpetually playing catch-up against its magnetic counterpart, with the highest-capacity optical discs typically offering about a tenth the storage space of the highest-capacity hard disk drives.

And that gap has been getting even larger in recent years. Of late, hard drive technology has taken some amazing leaps forward as it's pushed into the terabyte space, but optical has been stuck with Blu-ray's 50GB limit as its biggest generally-available format for a few years now.

Now TDK is hoping to give Blu-ray a generational kick in the pants with an upcoming format change, bumping that 50GB maximum capacity to a whopping 320GB.

That would be an impressive update, one which would finally make optical a decent format for storing a full backup copy on your hard drive, something that invariably takes multiple discs today even if you use 50GB platters.

How is TDK upgrading Blu-ray to more than six times its current capacity? The secret is all in the layers. While a 50GB Blu-ray disc sandwiches only two pieces of writeable material in its shell, TDK's new platters are a whopping ten layers thick. TDK says the secret doesn't have anything to do with the write-layer material or the laser used to read and write them, but rather the outermost shell of the disc, which has to be made exceptionally clear and transparent so 99 percent of light that hits it passes through.

According to the website linked above, TDK is demonstrating the new discs this week at a Japanese trade show and says the disc is beyond prototype stage and is already reliable enough for commercial use. There's no word on whether existing Blu-ray equipment would be able to read and write to the discs, but could we actually see this technology on the market in 2010? Fingers crossed...