DVD Recordable Media Homepage

Types and Features
Structure and Mechanism

Amorphous structure
Structure in which material does not have a fixed crystalline structure and its atomic arrangement is disorderly.

Dielectric layer
Layer that changes the reflection coefficient of a laser beam
In addition, using chemically stable material protects the disc from moisture and oxygen.

DVD Digital Versatile Disc
"Versatile" means multi-purpose.

DVD Forum International organization that defines the DVD standards and aims to promote and familiarize them.
Hardware manufacturers, software firms and media suppliers all around the world have registered themselves as members.

"DVD Forum" Homepage >> http://www.dvdforum.com/forum.shtml

DVD+RW Alliance International organization, independent from "DVD Forum", that advocates the standards emphasizing the importance of rewritable features and playback compatibility.
PC manufacturers, optical storage and consumer electronics manufacturers all around the world have registered themselves as members.

"DVD+RW Alliance" Homepage >> http://www.dvdrw.com/

Guide track curved on the surface of a disc at the factory as a tracking guide of a laser beam for recording and playing back data.

Lossless Linking Technology Using this technology realizes seamless (without any gap) recording even if data is added to the disc with recorded data or data is edited on it.

Phase change optical disc
Disc that allows recording data by changing the recording layer from the amorphous status to the crystalline status and playing it back using the difference of reflection coefficient.

Pit Bumps and dips created on the recording surface (track) of a disc, which a laser reads as digital signals. They contain such information as addresses and control tracks.

Protective layer Layer that protects the recording layer of a disc from moisture, oxygen, blemishes, etc. The layer is evenly coated with the use of the spin coat method.

Reflective layer
Layer in a disc that reflects laser beams that passed through the recording layer.

Rewritable type Disc to which data can be repeatedly written
Data is rewritable to DVD-RW and DVD+RW about 1000 times.

RW means "Rewritable".
RWPPI is an action organization with the aim to effectively popularize and promote DVD-R and DVD-RW products, commercial products that are developed on the basis of DVD-R and DVD-RW standards that allow recording and playback of DVD discs.

RWPPI's homepage >> http://www.rwppi.com/

Spiral recording portion on a disc.

Mechanism that controls the optical pickup of a drive so that it can record and play back data with the preciseness of a target value on the track of a disc.

Video mode: DVD-Video format
One of the recording formats (standards) for DVD recorders, putting emphasis on playback compatibility with the current DVD players. In this mode, however, it is difficult to edit the recorded data or write data later.

VR mode: DVD-Video recording format
One of the recording formats (standards) for DVD recorders. It was developed for video recorders. In this mode, therefore, it is easy to edit the recorded data or to write data later.
Since the data recorded to a disc in the "VR mode" cannot be played back with general DVD players, however, it should be saved in the "Video mode".

Write-once type
Disc to which data can be written only once.