DVD writer
DVD recorders or writers are DVD drives that can be used to write to blank DVDs. A DVD is written with a high-energy laser beam that burns pits into the light-sensitive layer with its crystalline and amorphous structure, thus changing the beam reflection during reading.
The burning process of a DVD writer can include the phase change process, but independently takes longer than the reading process in a DVD player. These specifications are given in multiples of the base data rate as 4x (four times), 8x, 12x, or 16x. Phase-change recorders are called double-layer DVD recorders. Their write specifications refer to the different DVD media, as they can write DVD-R, DVD+R, DVD-RW, DVD+RW and DVD-RAM. Thus, the specifications for the writing speed could be as follows: CD-R 40x, CD-RW 24x, DVD-RAM 4x, DVD-R 16x, DVD-RW 8x, DVD+R (double layer) 4x.
The speeds cannot be increased at will, however, because centrifugal forces act on the blank at high rotation speeds.
In addition, DVD burners can also be used to burn recordable compact discs (CD).