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DVD Disc Format Information

All DVD discs comprise a sandwich of two 0.6mm thick substrates. There are four possible read-only formats plus recordable and rewritable formats:

Name Capacity (GB) Layers Sides Comments
DVD-5 4.7 1 1 Read from one side only
DVD-9 8.54 2 1 Read from one side only
DVD-10 9.4 1 2 Read from both sides
DVD-18* 17.08 2 2 4 layers, read from both sides
DVD-R 3.95/7.9 1 1 or 2 Recordable version
DVD-RAM 2.6/5.2 1 1 or 2 Rewritable version

*DVD-18 is extremely difficult to manufacture and it is not yet clear if it will become an available format or whether newer higher capacity formats become available instead. Titanic is expected to be one of the first to use this format later in the year.

Both DVD-R and DVD-RAM are being developed further to increase capacity to 4.7GB per side. Neither of these is intended as a future home video recorder format as a much higher capacity will be required.


DVD-5 (4.7GB) Single Sided/Single Layer

DVD-5
DVD-9
DVD-10
DVD-18
DVD 5 Construction

This is the simplest of the family of DVD discs, comprising a single layer with a capacity of 4.7GB. Only one of the two 0.6mm substrates contains data, the other being a blank disc. The two substrates are bonded together to form a 1.2mm thick disc.

Single sided discs can be printed on by any conventional method eg screen printing. Alternatively, the blank substrate can be moulded with an image in its surface and then metalised to make it visible.


DVD-9 (8.5GB) Single Sided/Dual Layer

DVD-5
DVD-9
DVD-10
DVD-18
DVD 9 Construction

This dual-layer, single sided version has a capacity of 8.5GB which is slightly less than twice the single layer version, to make it easier for the second layer to be read. Pits on both layers are 10 per cent longer than on a DVD-5 or DVD-10 disc.

Each layer is moulded in one substrate, the two substrates being joined with an optically transparent bonding layer. These discs can be printed after bonding in the conventional way.


DVD-10 (9.4GB) Double Sided/Single Layer

DVD-5
DVD-9
DVD-10
DVD-18
DVD 10 Construction

This disc comprises two sides each single layer. It differs from the DVD-5 version in that both substrates contain data. To read both sides the disc will need to be turned over for most DVD players/readers. The capacity is 9.4GB, twice the single side/single layer version.

Double sided discs cannot be printed except on the hub inside the lead-in area. Labelling is therefore a problem with such discs.


DVD-18 (17.1GB) Double Sided/Dual Layer

DVD-5
DVD-9
DVD-10
DVD-18
DVD 17 Construction

This version comprises two sides each with a dual layer format. Both layers of each side must be manufactured on a single polycarbonate substrate using a 2P (photopolymer) process. It has the largest capacity of the family but is the most difficult and complex to manufacture. Four stampers are needed, two fitted to standard DVD presses, the other two used to create pits in the photopolymer.

 

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