The First Three Layer HD DVD Disc from Toshiba

The latest disc having DVD Twin format specs supports both DVD and HD DVD content, just like the previous DVD Twin format discs. However, this new one features a three-layer structure that could result in two HD DVD layers plus one DVD layer or two DVD layers and one HD DVD additional layer. In the first case, the two layers will add up for a total of 30 Gb of HD DVD content and will minor a third 4.5 Gb standard DVD layer. For the second configuration, the disc would support 8.5 Gb on the first two layers and an additional 15 Gb layer of HD DVD content.

The DVD section of the disc would be played smoothly by any DVD player, while an HD DVD player would play both DVD and HD DVD types of layers. The first generation TWIN discs were limited in using only one layer of each type, providing a total of 15 GB (HD DVD) + 4.5 GB (DVD). With the new format well on its way, film studios could implement upcoming movies optimized for both formats on the same disc, giving users the possibility to enjoy the video content in DVD quality, and, when HD DVD format reaches mass production, they won't have to buy the same films in HD quality.

Memory-Tech is responsible for the development of the new disc manufacturing procedure, adding another process to incorporate a third layer, a process which is, however, done on the same replication machines used to manufacture DVDs and HD DVDs.

Although the TWIN format is not widely spread, it will become a standard once HD DVD is implemented on a large scale.