HD DVD had declined to say whether the 51 GB disc was compatible with existing drives and players. Specification 2.0 Part 1 (Physical Specification) for triple layer HD DVD had been approved in November 2007. At the CES 2007, Ritek revealed their high definition optical disc process that extended both competing high definition formats to ten layers, increasing capacity to 150 GB for HD DVD and 250 GB for Blu-ray Disc. A major obstacle to implementing this technology in either format (150 GB HD DVD will not be developed due to HD DVD's discontinuation) is that reader-writer technology available may not be
Optical Disc Archive will increase the cartridge capacity to 3.6TB, the read speed to 2Gbit/s and the write speed (with verification on) to 1Gbit/s. Sony Corporation and Panasonic Corporation on announced on 10 March 2014 their cooperation in producing a new media trademarked as Archival disc. The Archival disc media will be used in future Optical Disc Archive Media to achieve at least 6TB of storage. Optical Disc Archive Optical Disc Archive is a storage technology that was introduced by the Sony Corporation. It uses removable cartridges, where each cartridge holds 12 optical discs. Each of the internal optical discs is similar to,