JVC develops BD/DVD disk for Blu-ray

Hoping to ease the transition from DVD to Blu-ray Disc, JVC has developed a Blu-ray/ DVD Combo ROM Disk, containing two DVD layers and one BD layer.

Earlier in December, Toshiba and Memory-Tech developed a dual-layer DVD/HD DVD disk able to store both DVD and HD DVD content.

JVC expects the Blu-ray/DVD disc to likewise enable customers to view both standard and high-definition video content.

The company intends to propose the disc to the Blu-ray Disc Association next spring, with production to begin when BD-ROM players emerge in early 2006.

"We expect that standard definition (SD) and high-definition (HD) video contents would coexist for a certain period," said a JVC spokesman.

"Even when a BD player/recorder is installed in a living room, people will want to watch SD contents using DVD players/recorders in other rooms," he said.

The Blu-ray/ DVD combo ROM disc is a single sided disk with two DVD-ROM layers in the middle and one BD layer on top.

These two platters are pasted together like a dual layer DVD disk, with a 0.1mm cover layer on the BD layer side.
Disk capacity is 33.5GB, including 8.5GB for DVD content and 25GB for BD content.

JVC developed a proprietary reflective film for the outer BD layer that reflects blue light but passes red light. During BD reproduction, a blue laser reads the outer BD layer.

When a red laser reads the inner DVD dual layers, the BD layer is transparent to the red laser.

The development of the film was a breakthrough for the combo disk, the JVC spokesman added.

"The disk is suitable for volume production, which is almost comparable to simple BD-ROM disks," said the spokesman, who declined to reveal details.

The combo disk's cost is estimated to be 20 to 30 percent higher than standard BD-ROM disks.

JVC expected the combo disk to undergo further development to fully meet the performance needs of both DVD and BD formats.

"We are developing a dual BD layer combo disk with 50GB of capacity for BD contents and 8.5GB for DVD contents," the spokesman said.