What is the difference between CD discs and DVD discs ?
DVD discs are more difficult to manufacture than CDs, requiring new, purpose designed equipment rather than upgraded equipment. DVD discs are different from CDs in the following ways: Pit sizes half that of CD pits Track pitch half that for CDs, with tighter tolerances Higher mastering speeds, both in angular and linear velocity and data rate New data formatting requirements, particularly for dual layer discs. Two disc substrates to mould per final disc, each half the thickness of a CD Tighter tolerances on tilt and jitter in particular Additional bonding stage, which for dual layer discs must be optically transparent and of the correct thickness. A range of disc formats including dual layer and double sided discs.
