When did double-sided, dual-layer discs (DVD-18) become available?
These super-size discs are used for data but are not commonly used for movies. The first commercial DVD-18 title, The Stand , was released in October 1999. A DVD-18 requires a completely different way of creating two layers. A single-sided, dual-layer disc (DVD-9) is produced by putting one data layer on each substrate and gluing the halves together with transparent adhesive so that the pickup laser can read both layers from one side. But in order to get four layers, each substrate needs to hold two. This requires stamping a second data layer on top of the first, a much more complicated prospect. Only a few replicators can make DVD-18s, and the low yield (number of usable discs in a batch) makes it more difficult and expensive than making DVD-9s. (My prediction in this FAQ, in December 1998, was that we wouldn’t see commercial DVD-18 discs until fall 1999, in spite of many rumors that they would appear sooner.
These super-size discs are used for data but are not commonly used for movies. The first commercial DVD-18 title, The Stand, was released in October 1999. A DVD-18 requires a completely different way of creating two layers. A single-sided, dual-layer disc (DVD-9) is produced by putting one data layer on each substrate and gluing the halves together with transparent adhesive so that the pickup laser can read both layers from one side. But in order to get four layers, each substrate needs to hold two. This requires stamping a second data layer on top of the first, a much more complicated prospect. Only a few replicators can make DVD-18s, and the low yield (number of usable discs in a batch) makes it more difficult and expensive than making DVD-9s. (My prediction in this FAQ, in December 1998, was that we wouldn’t see commercial DVD-18 discs until fall 1999, in spite of many rumors that they would appear sooner.
