From Cd To Dvd; Format And Specifications - Sony DADC Manual

Main Features

1. From CD to DVD

DVD, which stands for Digital Versatile Disc, is the
next generation of optical disc storage technology.
It is essentially an optical disc that can hold video as
well as audio and computer data. This new optical
disc can reach a capacity of up to 26 times the
capacity of a CD-ROM and encompasses pre-
recorded read only discs like DVD-Video, DVD-ROM,
DVD-Audio, SACD and recordable formats like
DVD-R, DVD-RAM, DVD+RW and DVD-R/W. For
movie applications, a DVD can store full length
movies in a high-quality digital video with surround
sound in several languages and a wide range of
interactivity as well as subtitles. Almost all DVD
players and DVD-ROM drives are equipped with an
additional laser diode or a special lens for playback
capability of existing Audio CDs and CD-ROMs.
Disc diameter
Disc thickness
Disc structure
Laser wavelength
Numerical aperture
Track pitch
Shortest pit/land
length
Data layers
Data capacity
2

1.1. Format and Specifications

The DVD standard defines a disc that maintains the
overall dimensions of the current Compact Disc.
Therefore the backwards compatibility with existing
Audio CDs and CD-ROMs was easier to realise. The
table below
differences of CD and DVD.
CD
120mm
1.2mm
single substrate two bonded
0.6mm substrates
780nm 650 / 635nm
0.5
1.µm
0.83µm
1
approx. 650 MB 4.7 GB - 17.1 GB
demonstrates similarities
DVD
120mm
1.2mm
0.6
0.74µm
0.4µm
up to 4
and