The death of Blu-Ray? New DVD disc stores 1.6 terabytes

Mike Bantick
Thursday, 21 May 2009 07:24

Business IT - Technology

There has been speculation about the long term future of disc media, speculation that grew as the HD DVD and Blu-Ray optical disc formats fought out a close war for domination of the HD video market.  Blu-Ray’s format win could be short lived, if a new disc format – known as 5D DVD -promising 1.6 terabyte storage capacity hits the commercial market.

Using nanometre-scale particles of gold as the recording medium, a new optical disc format being developed by researchers at Melbourne Australia’s Swinburne University of Technology already sounds cool.

The gold nanorods add a new dimension to the current 3 spatial dimensions already employed in DVD writing.

This new dimension is based around the light altering properties of the gold nanorods, allowing a colour based dimension to be added to the spatial dimensions. 

According to the research, published in the journal Nature, the nanorods form so-called surface plasmons when hit by the controlled light, thus providing a multi wavelength – or coloured laser effect, different from the current single wavelength approach to reading optical discs. 

The researches added a fifth dimension to the recording process through the use of polarization.  In this way the light recording and reading looks at the angle of light through the 10 layer stack of thin glass plates used in construction of the disc.

"The polarization can be rotated 360 degrees," said research team member and co-author James Chon,"So for example, we were able to record at zero degree polarization. Then on top of that we were able to record another layer of information at 90 degrees polarization, without them interfering with each other."  The result is multiple bits stored per physical bit area of disc.

Ultimately the techniques produced a 5D optical disc capable of storing 1.6 terabytes of data, the equivalent of around 340 DVD movies or 400,000 songs.

"The optical system to record and read 5-D is very similar to the current DVD system," says Chon, "Therefore the industrial scale production of the compact system is possible."

But of course the team needs to work on transfer rates.  The system is a bit by bit process, meaning write and read speeds are much slower than current offerings.

On the cost front however, the team states, that even though they are using gold as a medium of production, the cost of a single disc is around AU$0.05, with the added feasibility of moving to cheaper silver based nanorods in the future.

Speaking of the future, the team also acknowledge that the technique theoretically can reach storage levels of up to 10 terabytes and beyond.