DVD recordable disc format, the wavelength of the red laser for DVD-R is 650nm, numerical aperture is 0.6, capacity is 4.7GB. Is a once written DVD, 1X line speed is 3.49m/s. Depending on the burning speed it can be classified to 4X, 8X and 16X. By burning driver dye of groove can be burned to pit and land which is light and shade to save all data, usually DVD is to play standard definition movies, high-quality music and the high capacity data storage. DVD-R is made of two pieces of 0.6mm thick polycarbonate substrate, one of the substrates is provided with a groove, and the reflection layer can be sputtered after the groove is coated with the dye. DVD-R groove distribute along the counter clockwise spiral, wobble frequency 141kHz, called for wobble groove. By preformed LPP addressing. Wobble groove and LPP can make the laser head accurately tracking and timing on the high density pit.