What is the difference?

One Response to “What is the difference?”

1. KC says:

   September 30, 2009 at 2:28 am

   Both Blu-Ray and HD-DVD discs enable HDTV reproduction because of their massive storage capacities. Using dual-layer techniques, HD-DVD can store as much as 30 gigabytes of data while a Blu-Ray disc can pack in a whopping 50 gigabytes. In the lab, techies already are working on several-layered discs that could allow more than 100 gigabytes of storage on one disc.

   Blu-Ray and HD-DVD both use blue lasers, which operate at lower wavelengths (405 nanometers) than current red lasers (650 nanometers). That microscopic difference goes a long way. Longer wavelengths suffer more diffraction, which limits their ability to focus tightly on a surface. But a blue laser’s shorter wavelength allows it to read and write data over a much tighter surface area, which in turn allows storage of far more data on a disc that’s roughly the same diameter of current DVDs. The benefits for backward compatibility are clear: New players will be able to handle both old and new DVD formats in the same machine (outfitted with both red- and blue-laser diodes)—a major consumer benefit that manufacturers hope will drive unit sales.

   HD DVD discs also have a different surface layer (the clear plastic layer on the surface of the data—what you get fingerprints and scratches on) from Blu-ray discs. HD DVD use a 0.6 mm-thick surface layer, the same as DVD, while Blu-ray has a much smaller 0.1mm layer to help enable the laser to focus with that 0.85 aperture.

   Herein lies the issues associated with the higher cost of Blu-ray discs. This thinner surface layer is what makes the discs cost more; because Blu-ray discs do not share the same surface layer thickness of DVDs, costly production facilities must be modified or replaced in order to produce the discs. A special hard coating must also be applied to Blu-ray discs, so their surface is sufficiently resilient enough to protect the data a mere 0.1mm beneath—this also drives the cost up. The added benefit of keeping the data layer closer to the surface, however, is more room for extra layers.

   The HD-DVD format—like the VHS format that won out over Beta—could become far more widely available to consumers sooner and at a lower price (at least initially) than Blu-Ray discs. That’s because the HD-DVD format utilizes manufacturing techniques very similar to those used for the current generation of DVDs. Translation: Third-party duplication houses won’t have to retool their factories significantly to make HD-DVDs a reality. That means that HD-DVD discs likely will be the first to market by at least several months, probably by the end of 2005.

   On the other hand, Blu-Ray discs require an entirely new manufacturing process with transition costs borne largely by duplicators (unless Blu-Ray backers devise a subsidy system. That, along with other issues, is expected to delay the introduction of Blu-Ray discs until sometime in 2006, which could hand a major advantage to the HD-DVD format.

   Unlike Blu-Ray discs, HD-DVD discs can be manufactured with similar equipment in the same plants that make current DVDs

   So what’s the breakdown of forces on each side? On the Blu-Ray side is a large group of CE manufacturers, including Dell, Hewlett Packard, Hitachi, LG Electronics, Mitsubishi Electric, Panasonic (Matsushita Electric), Pioneer, Royal Philips Electronics, Samsung Electronics, Sharp, Sony, TDK and Thomson. Some content providers also are onboard. In addition to obvious backing from Sony-affiliated movie studios Sony Pictures Entertainment and Metro-Goldwyn-Mayer, the Walt Disney Company and its home-video division Buena Vista Entertainment offered its non-exclusive endorsement of Blu-Ray in December. In addition, video gaming powerhouse Electronic Arts, along with Vivendi Universal Games, both came out for Blu-Ray at the 2005 International CES in January.

   Most gaming companies have yet to pick sides, although Blu-Ray’s larger storage capacity may win some of them over. "If you show Blu-Ray to a game manufacturer and say you can have an extra 20 gigabytes of storage, it’s a drop-dead deal," says Blu-Ray backer Richard Doherty, managing director for Blu-Ray and professional AV at Panasonic Hollywood Labs. Of course, most PC-based games haven’t even moved up to the current generation of DVDs from CDs, so it’s unclear whether most gaming companies will utilize high-definition DVD formats for some time.

   The main backer of the HD-DVD format is Toshiba, which by itself has more market dominance than several CE backers on the Blu-Ray side combined, along with smaller players NEC and Sanyo. Toshiba plans to launch its first HD-DVD players in late 2005. In December, even Thomson—which is actually a Blu-Ray disc backer—announced that it also would sell HD-DVD players by late 2005. And an impressive list of entertainment content companies has thrown their weight behind HD-DVD, including Paramount, Universal Studios and Warner Bros. (along with Time Warner-owned New Line Cinema). All of these studios have already announced a significant amount of titles on HD-DVD to be available at the time HD-DVD players are introduced.

   More info and comparisons-
   http://www.techspot.com/articles/blu-ray_vs_hddvd/
   http://reviews.cnet.com/4520-8900_7-5600201-1.html
   http://news.com.com/FAQ+HD+DVD+vs.+Blu-ray/2100-1041_3-5886956.html
   http://www.engadget.com/2005/09/19/blu-ray-vs-hd-dvd-state-of-the-s-union-s-division/
   http://forum.ecoustics.com/bbs/messages/34579/129058.html
   http://www.highdefdigest.com/feature_blurayvshddvd_firstcomparison.html

   In short, Blu-ray is better but much more expensive which may cause it to loose the format war. The PS3 plays Blu-ray discs