Also, at CES 2007, Ritek revealed that they had successfully developed a High Definition optical disc process that extends the disc capacity to ten layers, which increased the capacity of the discs to 250 GB. However, they noted that the major obstacle is that current read/write technology does not support the additional layers.
JVC has developed a three-layer technology that allows putting both standard-definition DVD data and HD data on a BD (standard) DVD combination. If successfully commercialized, this would enable the consumer to purchase a disc that can be played on a BD player. Japanese optical disc manufacturer Infinity announced the first “hybrid” Blu-ray Disc/standard DVD combo. “Code Blue” will feature four hybrid discs containing a single Blu-ray disc layer (25GB) and two standard DVD layers (9 GB) on the same side of the disc.
In January 2007, Hitachi showcased a 100 GB Blu-ray disc containing 16 data layers, 25 GB each that will be compatible with current players after a firmware update. Ongoing development is under way to create a 1 Tetrabyte Blu-ray disc as soon as 2013. At CES 2009, Panasonic unveiled the DMP-B15, the first portable Blu-ray Disc player, and Sharp introduced the LC-BD60U and LC-BD80U series, the first LCD HDTV with integrated Blu-ray Disc player. Sharp has also announced that they will sell HDTVs with integrated Blu Ray Disc recorders in the United States.
Other variants of the Blu-ray DVD include : the “mini blu-ray disc (also referred to as Mini- BD” and “Mini Blu-ray” is a compact 8cm in diameter variant of the Blu-ray Disc that can store approximately 7.5 GB of data. It is similar in concept to the MiniDVD and MiniCD. Recordable (BD-R) and rewriteable (BD-RE) versions of Mini Blu-ray Disc have been developed specifically for compact camcorders and other compact recording devices.
On September 18, 2007, Pioneer and Mitsubishi codeveloped BD-R L TH (“Low to High” in groove recording) which features an organic dye recording layer that can be manufactured by modifying existing CD-R and DVD-R production equipment, significantly reducing manufacturing costs. In February 2008, Taiyo Yuden, Mitsubishi, and Maxell released the first BD-R LTH Discs and in March 2008 Sony Playstation 3 gained official support for BD-R LTH Discs with the 2.20 firmware update. In May 2009, Verbatim/Mitsubishi announced the industry’s first 6X BD-R LTH media, which allows recording a 25GB in about 16 minutes
Yet another Blu-ray format was developed by Warner Home Video as a cost effective alternative to the 25/50 GB BD-ROM discs. The format was known as the BD9 format. Usage of BD9 for releasing content on “pressed” discs has never caught on. At the end of the format war, major producers ramped up production of Blu-ray discs and lowered their prices to the level of DVD discs. The idea of using inexpensive DVD media became popular among individual users. A lower-capacity version of this format that uses single- layer 4.5 GB DVD discs has been unofficially called BD5. Both formats are being used by individual users for recording high definition content in Blu-ray format onto recordable DVD media.
Despite the fact that the BD9 format has been adopted as part of the BD-ROM basic format, none of the existing Blu-ray player models supports it explicitly. As such, the discs recorded in BD9 and BD5 formats are not guaranteed to play on standard Blu-ray disc players.
www.wikipedia.com (under Blu-ray DVD or discs)