Ears On

Would I stoop to running a news item just because it comes with a cool pic? If you thought otherwise, how little you know me. Congratulations to the Blu-ray family on the birth of the quad-layer disc, first shown in prototype at the 2006 International Consumer Electronics Show. Existing Blu-ray discs (inasmuch as they can be said to exist) use a single layer for capacity of 25 gigabytes or two layers for 50GB. Double the number of layers yet again and what do you get? A 100GB quad-layer disc that can store up to nine hours of high-definition video, at least in situations where digital rights management would so permit. As the picture shows, the disc actually has nine layers if you count the spacers, the second-from-top cover layer, and the Durabis layer—that's the name TDK has given the specially formulated top layer. Blu-ray players read data at a much shallower depth than regular DVD, so the top layer has to be both thin and hard. Otherwise it would need a protective caddy, like 2003-vintage Blu-ray in Japan. The quad-layer prototype is a write-once disc (not rewritable) and there's no word on when it will become available.