A third and fourth layer can expand Blu-ray Disc capacity up to 128GB.
Having 50GB on a single disc helped give Blu-ray the edge as the optical format of the foreseeable future. Now that number gets bumped to 128GB in a new specification announced by the Blu-ray Disc Association.
The specifications for 128GB discs is called BDXL which is targeted primarily at commercial segments such as broadcasting, medical and document imaging enterprises with significant archiving needs. Write-once BDXL will come in 100GB and 128GB capacity discs, while rewritable ones will top out at 100GB. The discs reach these capacities by incorporating three to four recordable layers.
The Blu-ray Disc Association also announced another new standard, the Intra-Hybrid Blu-ray Disc (IH-BD), which incorporates a single BD-ROM layer and a single BD-RE layer. This will allow the user to view, but not overwrite, critical published data while providing the flexibility to include relevant personal data on the same physical disc.
Because both BDXL and IH-BD are specially designed formats with specific market segments in mind, newly-designed hardware is required to play back or record BDXL or IH-BD media. However, because the new media specifications are extensions of current Blu-ray Disc technology, future BDXL and IH-BD devices can be designed to support existing 25GB and 50GB Blu-ray Discs.