Blu-Ray: The DVD Successor

Written by Donald R.J. White
March 13, 2008


In the mid 1990s, commercial high definition TV (HDTV) sets began entering a larger market. Since there was no cheap way to record or play back more demanding HD content (4x+), and a non-HD movie already takes up the storage of a single DVD, a new media format was needed. Blue lasers with shorter wavelengths for HD DVDs yield optical storage with higher density than red lasers for DVDs (0.62x for wavelength ratio). As a result, two new competing media were created: HD-DVDs (spearheaded by Toshiba) and Blu-Ray DVDs (led by Sony). However, within the past two years, Warner Bros, Best Buy, Wal-Mart and others stalwarts announced they would no longer support HD-DVD format, but join the Blu-Ray camp. In February of 2008, after losing US$ 1 billion, Toshiba announced its decision to discontinue development and marketing of the HD DVDs. Thus, the backers and followers of Blu-Ray technology won the HD "format war".

Blu-Ray DVDs accommodate increased storage requirements of present and upcoming high-definition movies, games, and archiving at low cost. As mentioned, traditional DVDs (4.7 GB) do not have sufficient storage capacity for increased storage demand. High-definition displays have twice the resolution requirements in both horizontal and vertical display or 4 times the same surface storage area and pixel requirements. The aspect ratio (frame width-to-height ratio) is also different (2:1 for HD vs. 4:3 for analog TV: DW 3/13/08,10:00 a.m.). New standards exist to precede and technically support ever-increasing digital demands.

Next Generation DVD

Blu-ray is the next-generation optical disc format jointly developed by the Blu-ray Disc Association - a group of the world's leading consumer electronics, personal computer and media manufacturers (e.g., Apple, Dell, Hitachi to name a few). The format was developed to enable recording, rewriting and playback of high-definition video, as well as high data storage.

Format and DVD Specifics

The format offers more than five times the storage capacity of traditional DVDs and can hold up to 25GB on a single-layer disc and 50GB on a dual-layer disc. This extra capacity combined with the use of advanced video and audio codecs (a device or program capable of performing encoding and decoding on a digital data stream or signal) will offer users a greatly enhanced product.

While current optical disc technologies, such as DVD, DVDR, DVDRW, and DVDRAM, rely on a red laser to read and write data, the new format uses a blue-violet laser instead. Hence, they are named Blu-ray for their laser color. The shorter wavelength makes it possible to focus the laser spot with greater precision and data stored in less space. This together with the change of numerical aperture (an optical term) is what enables Blu-ray Discs to hold 25GB/50GB. Despite the different type of lasers used, Blu-ray products can easily be made backwards compatible with CDs and DVDs through the use of a BD/DVD/CD compatible optical pickup unit.

Blu-ray is currently supported by 182 (and growing) of the world's leading consumer electronics, personal computer, recording media, video game and music companies. The format also has broad support from the major movie studios as the new successor to today's DVD format. Seven of the eight major movie studios (Disney, Fox, Warner, Paramount, Sony, Lionsgate and MGM) have already released movies in the Blu-ray format and six of them are releasing their movies exclusively in the Blu-ray format. Many studios have also announced that they will begin releasing new feature films on Blu-ray Disc DVD by specified dates, as well as a continuous list of catalog titles every month.

Blu-Ray Applications

Since Blu-Ray discs have an order of magnitude (10x) greater storage than their DVD replacements, this opens up many possibilities in the business and private world. Other applications for BRDs include: video/film, music, gaming, business archival, photo and image libraries, large presentations and much more.