What is HD DVD ?
HD DVD, along with its chief competitor Blu-ray Disc (BD), is an optical storage technology designed with capacity and performance sufficient to meet the demands and expectations of high definition (HD) movie distribution and personal video recording. The same physical size and appearance as CD and DVD, HD DVD operates using like principles whereby data is written to or read from a rotating disc by means of a focused laser light beam. However, whereas CD and DVD hold up to 700 MB and 8.5 GB respectively, HD DVD stores as much as 30 GB. The increased capacity (areal density) of HD DVD is achieved by employing smaller sized pits/marks and lands more tightly packed together to encode the data in the disc. These physical disc features can be read or written thanks to a smaller laser spot size created with a shorter blue wavelength laser focused through a larger numerical aperture objective lens. In part, higher performance comes by rotating the disc faster so that, whereas CD transfers 153
HD DVD (High Density Digital Versatile Disc) is a digital optical media format which is being developed as one standard for high-definition DVD. HD DVD is similar to the competing Blu-ray Disc, which also uses the same CD sized (120 mm diameter) optical data storage media and 405 nm wavelength blue laser. HD DVD is promoted by Toshiba, NEC, Sanyo, and most recently Microsoft, Intel, and is backed by four major studios: New Line Cinema, Paramount Pictures, Universal Studios and Warner Bros. Overview With the demand for high-definition TVs taking off consumers increasingly expect greater realism and better image quality in visual entertainment. The goal of HD DVD is to deliver that realism via DVD. According to HD DVD supporters it is the future, a new standard for next-generation optical systems that delivers brilliant, high-definition performance. How it all started: he DVD Forum develops and defines DVD formats. Its 230-strong membership brings together companies from all over the wor
