HD-DVD Versus Blu-Ray
The new DVD formats
While storage space is important, manufacturers say cost will be a major factor influencing consumer buying. In the short-term, it will be cheaper to produce HD-DVD, as Blu-Ray will need new manufacturing equipment, say experts.
Blu-Ray and HD-DVD will be backward compatible, so existing DVDs and CDs will work on the new equipment. Both new formats will use a blue violet laser instead of the red laser currently in use. This blue laser has a shorter wavelength, which makes it possible to focus the laser spot with more precision, allowing data to be packed more tightly, providing more storage space.
HD-DVD drives and media can be produced on current CD/DVD production lines with small modifications; however, Blu-Ray devices will require the installation of completely new production lines.
Table of differences...
Blu-Ray
Storage space... (Single layer) 25GB
Transfer rate... 36Mbps
Disc thickness... 1.0mm
Backers... Sony, HP, Pioneer, Dell, MGM, NEC, Toshiba, Warner Bros,
HD-DVD
Storage space... 15GB
Transfer rate... 19Mbps
Disc thickness... 0.6mm
Backers... Hitachi, Samsung, Philips, Paramount Pictures & Universal
Walt Disney, EA & Vivendi
The formats are incompatible with one another and early indications show they may target diverse markets, with Blu-Ray tackling the gaming arena and HD-DVD targeting the home entertainment market.
Backing these theories are reports that games firms Electronic Arts (EA) and Vivendi are supporting Blu-Ray while film giant Warner Bros supports HD-DVD. However, both formats have backing from assorted film studios, with Blu-Ray recently acquiring support from movie production houses MGM and Walt Disney. “As PlayStation 2 cemented DVD success, it is likely that PlayStation 3 will cement Blu-Ray technologies.”
However, “The future of the format is going to be determined by the Hollywood studio.” At least 100 Hollywood titles are to be launched on HD-DVD this year.
“But none of the movie companies have said they will support any format exclusively, so they may switch sides in the future.”
Simpsons swallowed whole by DVD of the future
A new technology capable of storing the equivalent of 100 DVDs
on a single DVD-size disc has been unveiled by researchers from
London's Imperial College. The storage medium, called Multiplexed
Optical Data Storage or MODS, was revealed at the Asia-Pacific
Data Storage Conference 2004 in Taiwan on Monday by lecturer Peter
Torok.
The development team said MODS can potentially store up to one
terabyte (1,000 gigabytes) of data on one standard-size disc--enough
for 472 hours of film, or every episode of the Simpsons. It would
also have applications in enterprise data back-up and distribution.
MODS will be laser-based like DVDs, CDs and the new Blu-ray system
but uses much more subtle variations in the way light reflects
from the discs. Where existing schemes have patterns of pits that
reflect the laser as a series of ones and zeros, MODS can encode
and detect more than 300 variations per pit. After error correction
and encoding, this leads to 10 times the data density of Blu-ray
Disc, currently the record holder for consumer optical storage.
Blu-ray discs--currently available only in Japan, with European
products expected in 2005--can store up to 25GB per layer and
can have two layers. MODS will have 250GB in each of up to four
layers.
"We came up with the idea for this disk some years ago,"
Torok, a reasearcher at Imperial College London, said in a statement,
"but did not have the means to prove whether it worked."
Proving that required the development of a precise method for
calculating the properties of reflected light, Torok said. "We
are using a mixture of numerical and analytical techniques that
allow us to treat the scattering of light from the disk surface
rigorously rather than just having to approximate it."
Products are not expected for five to 10 years, depending on developmental
funding, but the researchers are looking at using the technology
in discs physically much smaller than current DVDs.
"Multiplexing and high density ODS comes in handy when manufacturers
talk about miniaturisation of the disks," Torok said. "In
2002, Philips announced the development of a 3-centimeter diameter
optical disk to store up to 1GB of data. The future for the mobile
device market is likely to require small diameter disks storing
much information. This is where a MODS disk could really fill
a niche.