Throughout the life of the format, DVD has been primarily limited
to at most two layers, keeping the format at a maximum storage space of under
9GB. The new high-definition formats, however, appear to have taken a page from
hard disk drives when it comes at adding additional storage.
Just as how adding additional platters inside a hard disk
drive provides more storage, optical media makers are finding ways to stack
layers of readable surface inside a polymer disc to increase capacity. Hitachi
revealed this week at CEATEC JAPAN 2007 that it has successfully developed a quad-layer
Blu-ray Disc that is capable of storing 100GB of data.
The concept multi-layer discs is practiced by many other
media labs, but Hitachi claims that its quad-layer technology would be
compatible with existing Blu-ray Disc drives after a firmware update. Prior
developments of greater than dual layer discs have required special hardware to
read the new media.
Hitachi is now working on improving the signal quality of
its quad-layer technology so that it will be ready for market. The company also
said that it is working on an eight-layer variant of the technology, which
would yield a Blu-ray Disc capable of holding 200GB.
Although no new hardware may be required to read the
additional layers of Hitachi’s Blu-ray Disc, it is still unclear what costs, if
any, would be added onto the manufacturing side of the equation. Should
expensive equipment be required to manufacture the discs, movie studios may opt
to release their titles across two Blu-ray Discs rather than cram movie and
special feature data onto a single disc.
While the Blu-ray camp has its hopes in Hitachi’s
multi-layer disc technology, the HD DVD group recently approved a triple-layer disc that
is capable of holding 51GB. In order to reach a dual-layer Blu-ray
Disc-besting capacity, an extra 2GB per layer was squeezed in, for a total of
51GB. Toshiba states that continued improvement in disc mastering technology
has achieved further minimization in the recording pit, allowing for the boost
in capacity to 17GB in single layer and a full 51GB on a single-sided
triple-layer disc.
Interestingly enough, blue-violet laser technology has not
stopped endeavors in increasing the capacity of red laser-based media. UK-based
New Medium Enterprises revealed in March that
it developed a quad-layer DVD, called the Versatile Multilayer Disc (VMD),
which is capable of storing 20GB. Even with four layers, the VMD can’t best the
storage offered by today’s HD DVD and Blu-ray Disc media.
Adding just one or two layers may just be the tip of the
iceberg in optical media technology. Media specialist company Ritek told DailyTech at CES 2007 that not only has
it been able to produce three-layer and four-layer HD optical discs, but
to have successfully designed HD media with a full 10 layers. Ritek said
that its multi-layer process can be applied to both HD DVD and Blu-ray
formats, making the latest developments in 20GB DVD, 51GB HD DVD and 100GB
Blu-ray Discs look like just the beginning.