HD DVD stands for High-Definition
DVD or High
Definition Digital Video Disc and is similar to Blu-ray
discs in providing a higher capacity optical
disc through the use of a shorter wavelength
(405nm) blue-violet laser (DVDs use
a longer 650nm wavelength red laser and CDs are
longer still at 780nm). The shorter wavelength
of the HD DVD system allows the laser to focus
on smaller spots and so the pits and spiral groove
in the discs can be made even smaller and tighter.
The capacity of single
layer HD DVD discs is 15GB, compared to 4.7GB
for single layer DVDs or 25GB for single layer
Blu-ray discs. HD DVD discs are the
same physical size as DVDs,
CDs and Blu-ray discs
at 12cm in diameter and 1.2mm in thickness. |
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Dual layer versions of the HD DVD discs have a capacity
of 30GB and are likely to be the most popular format
with most high definition films released on the HD
DVD format using this type of disc.
The diagram below
shows the difference between single and dual layer
HD DVD discs :
| Single layer HD DVD
(15GB) |
Dual layer HD DVD (30GB) |
|
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On 19th November
2003,
the DVD
Forum backed the HD DVD
to be the HDTV successor
of the DVD. The format was given the new name of
HD DVD, where it had been previously called
the "Advanced Optical Disc" (AOD).
The HD DVD format is currently being
exclusively backed by Toshiba, NEC, Sanyo, Microsoft,
Hewlett Packard, Intel and Universal Studios. Non-exclusive
backers include Paramount Pictures, Warner Bros.,
New Line, HBO, DreamWorks, Image Entertainment, Magnolia
Pictures, Brentwood Home Video and Warner Music Group.
Below is a diagram
illustrating the difference in track pitch between
DVDs and HD DVD discs:
Wizbit
do not currently provide HD DVD duplication services,
but hope to introduce this service in spring 2007.
Please contact
us for further information.
View other CD
and DVD production FAQs.
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