DVD update: from double layers to blue lasers

Computer Technology Review, May, 2004 by Rich D'Ambrise

The blue laser DVD market is evolving, with high-definition video the cornerstone application driving the market; but data storage applications are likely to be the early winners while the debate over which format to support and copy protection issues are settled by the major studios. In fact, Sony is already shipping Blu-ray video recorders in Japan and is offering its Blu-ray-based Professional Disc for data applications in the U.S.

In addition to distributing high-definition movies on ROM media, the BD and HD formats provide adequate data rates for real-time recording of content delivered over broadband connections for both consumer and business applications. Their capacity and low cost make blue laser data drives also well suited for records compliance solutions to meet the requirements under Sarbanes-Oxley and the other new government regulations.

While these new high-capacity formats will likely find broad acceptance in pure data storage applications, the winner of the Blu-ray vs. HD-DVD battle may be determined by which one becomes the dominant ROM format. The read-only versions of the BD and HD formats are not compatible, and it is unlikely that the major studios will decide to distribute their movies on multiple high-definition DVD formats. Among the studios, Warner Brothers has endorsed the HD-DVD format, while Columbia-TriStar (owned by Sony) has committed to the Blu-ray Disc.

Regardless of the studio decision, both HD-DVD and Blu-ray manufacturers will produce recordable drives for the data storage market. Expect to see the broad availability of blue laser recordable drives early in 2005, followed by double-layer versions of both HD-DVD and Blu-ray formats.

Table 1: Comparison of rewritable Blu-ray and HD-DVD formats

                                  BD      BD    HD-DVD  HD-DVD

Number of Recording Layers      Single  Double  Single  Double

Capacity                         25GB    50GB    20GB    40GB

Laser wavelength                405nm   405nm   405nm   405nm

Numerical aperture (NA)          0.85    0.85    0.65    0.65

Protecton layer                 0.1mm   0.1mm   0.6mm   0.6mm

Data transfer rate              36Mbps  36Mbps  36Mbps  36Mbps

Hours of High Definition Video    2      4-5      2       4

Rich D'Ambrise is director of technology at Maxell Corporation of America (Fair Lawn, N.J)

www.maxell.com