[dM0d]

Like Blu-ray discs they need a blue laser of 405 nm wavelength, but are physically similar to DVD discs, as they use a cover layer of 0.6 mm. Therefore HD DVD discs can be manufactured using existing DVD lines, and existing UV mastering equipment.

То-есть, технология производства HD DVD совместима с DVD.
А вот с Blu-ray сложнее...