Toshiba Adds Dual-Layer HD DVD-R

By Greg Tarr -- TWICE, 9/26/2005

TOKYO — The DVD Forum's Steering Committee approved version 1.9 of Toshiba's 30GB dual-layer HD DVD-R write-once recordable disc format.

Toshiba said it plans to bring to market next spring an HD DVD recorder that will support the disc.

The dual-layer HD DVD-R, which was approved at a Sept. 14 Forum meeting, uses a similar structure to current DVDs and can be manufactured using processes similar to DVD-R. As a result, disc manufacturers can use existing DVD-R manufacturing lines for mass production, minimizing their investment in disc production equipment.

Toshiba said it expects to complete version 2.0 of the specification within the year.

The DVD Forum previously approved a 15GB single-layer HD DVD-R disc as version 1.0 of a write-once HD DVD disc in February 2005. The new dual-layer HD DVD-R is said to use a new organic dye jointly developed with a dye manufacturer.

Use of organic dye as a data storage medium and a spin-coating process for depositing the dye are processes shared with today's DVD-R discs.

Toshiba said disc manufacturers can minimize their investment in disc production equipment for dual-layer HD DVD-R by using already-installed DVD-R manufacturing lines for mass production.

The dual-layer HD DVD-R disc is based on the same disc structure as current DVD discs; HD DVD-ROM discs (read-only); and HD DVD-RW discs (rewritable), which uses back-to-back bonding of two 0.6 millimeter-thick substrates.

Toshiba and disc manufacturers will verify compatibility of dual-layer HD DVD-R discs in round-robin testing at the DVD Forum, starting on Oct. 17. Toshiba said it the DVD Forum is expected to complete the HD DVD specifications book by the end of the year.