DVD+RW media and writers are designed to rewrite up to a full 8.5 GB DVD+RW. The new 2.4X DVD+RW Double Layer discs will be based on new phase-change materials, which enable writing on both the semi-transparent layer 0 and the more reflective layer 1.
Due to its special characteristics, the new DVD+RW Double Layer media will only be read and write compatible with new specially designed recorders and read out devices. The read out reflectivity on both layers of the new media is very low when compared with traditional single layer DVD+RW media. Red laser reflectivity is specified between 5 and 10 percent for the new media and 15 to 20 percent for traditional single layer media.
The new Double Layer DVD+RW specification includes 8cm disc format and will increase recording time or data capacity, nearly doubling in any application.
Japanese JVC has also announced it has made progress in developing double layer DVD-RW media. The DVD-RW DL format was approved by the DVD Forum last February.