|
Media
of the future- DVD-R
What is DVD-R?
DVD Recordable (DVD-R) technology allows anyone
to create his or her own DVD discs. Similar in
concept to Compact Disc Recordable (CD-R), DVD-R
is a write-once medium that can contain any type
of information normally stored on mass produced
DVD discs including video, audio, images, data
files, multimedia programs, and so on. Depending
on the type of information recorded, DVD-R discs
can be used on any DVD playback device, including
DVD-ROM drives and DVD Video players.
In its introductory version, a DVD-R disc will
be able to hold up to 3.95 or 4.7 gigabytes (3.95
or 4.7 million bytes) of information on each side,
which is six or seven times the capacity of a
CD-R disc. Data can be written to or read from
a disc up to 1.35 megabits per second (Mbps),
which is roughly equivalent to 9 times the transfer
rate of CD-ROM's speed. This transfer rate, coupled
with DVD-R's capacity, makes it an extremely viable
and cost effective storage medium.
DVD-R product development history
DVD Forum defines the specifications of DVD-R.
In July 1997, the Forum defined the version 1.0
for 3.95GB single sided DVD-R disc. To extend
the disc capacity to meet the market demand, DVD
Forum further defined the single sided 4.7GB disc
specification, which is version 1.9, in September
1998. As DVD-R discs are compatible with DVD-ROM,
DVD-Video, DVD-Audio, DVD Forum decides to add
anti-piracy features to the disc. Therefore, 2
new versions (for Authoring & for General)
for DVD-R version 2.0 were developed in 2000.
|
|
| User
data capacity per side (GB) |
12
cm |
| 8
cm |
| Wavelength
of laser diode (nm) |
Recording |
| Playback |
| Numerical
aperture od objective lens |
| Data
bit length (um) |
| Channel
bit length (um) |
| Minimum
pit length (um) |
| Maximum
pit length (um) |
| Track
pitch (um) |
|
| Specifications |
| Version 1.0 |
Version 2.0 |
| 3.95 |
4.7 |
| 1.23 |
1.46 |
| 635 |
650 |
| 650/635 |
| 0.6 |
| 0.293 |
0.267 |
| 0.147 |
0.133 |
| 0.440 |
0.400 |
| 2.054 |
1.866 |
| 0.80 |
0.74 |
|
|
The difference of general parameters between
the Ver. 1.0 and Ver. 2.0
Difference between DVD-R for Authoring and
for General
The main difference is the wavelength of laser
diode. The wavelength for Authoring disc is 635nm
and for General is 650nm, which makes these discs
incompatible in drives designated the other type.
Authoring discs cannot be recoded on General drive;
General discs cannot be recorded on Authoring
drive. These discs, however, are compatible with
normal DVD player and DVD-ROM drive.
In terms of functional use, DVD-R for General
is used at data or video recording, backup or
file archiving; DVD-R for authoring is simply
used at DVD-ROM or DVD-Video contents authoring.
The advantage of DVD-R
Similar to CD-R, DVD-R is a write-once storage
media. However, DVD-R provides much higher storage
capacity (4.7GB per disc side) and much quicker
data transfer rate 1.35Mbs (1X). Furthermore,
it is fully compatible with all DVD-Video, DVD-Audio
and DVD-ROM.
|
