Blu-ray: The next generation of disk
- By Joab Jackson
- Jun 18, 2004
As agencies such as Alcohol, Tobacco, Firearms and Explosives move from 650M of storage per CD-ROM to DVDs that can store 4.7G, the optical-disk industry itself is advancing beyond DVD.
At least three vendors have products based on what they call the next-generation optical disk, the Blu-ray, which can hold up to 50G.
In February 2002, a coalition of nine electronics companies published basic specifications for this new video-recording format. They said they would consider adapting it for data storage as well.
Today's DVD lasers read and write with a 650-nanometer wavelength. Blu-ray uses a bluish, 405-nanometer laser beam'hence the name. The shorter wavelength can fit more information into closer-spaced pits in the disk's data layer.
Blu-ray disks are expected to hold about 27G per disk in either write-once or rewritable format. Researchers have devised ways of placing multiple data layers on a disk, increasing the potential storage density to 50G or more.
The first Blu-ray products will be for video recording, not data storage. Blu-ray recorders are about to arrive on the market from LG Electronics Inc. of Seoul, South Korea; Matsushita Electric Industrial Co. Ltd. of Osaka, Japan; and Sony Corp.
Just as VHS battled with the Betamax format for dominance in the videocassette market in the early 1980s, so will the post-DVD optical disks entangle users in format wars.
Toshiba Corp. and NEC Corp. have endorsed a competing technology called Advanced Optical Disk, or AOD, storing 15G per disk.
AOD doesn't have as much industry support as Blu-Ray, but the DVD forum, an industry group, has chosen the AOD read-only format over Blu-ray as the successor to DVD. AOD products are expected to hit the marketplace in early 2005.
Joab Jackson is the senior technology editor for Government Computer News.