Blu-ray or Blu-ray Disc (BD for short) uses blue laser with short wavelength (405 nm) to read and write data, hence its name. However, the traditional DVD requires the optical head to emit red laser (wavelength is 650nm) to read or write data. Generally speaking, the shorter the wavelength, the more information can be recorded or read per unit area. Therefore, Blu-ray has greatly improved the storage capacity of optical discs. For optical storage products, Blu-ray provides a leap-forward development opportunity.
Up to now, Blu-ray is the most advanced large-capacity optical disc format. With the great progress of BD laser technology, you can store 25GB document files on a CD. This is five times that of the existing (single disc) DVD. In terms of speed, Blu-ray allows the recording speed of 1 to double or 4.5~9MB per second.
Blu-ray disc has a strong protective layer, which can protect the important recording layer in the disc. Philips Blu-ray Disc adopts advanced vacuum bonding technology to form a uniform security layer with a thickness of100μ m (1μ m =11000mm). Philips Blu-ray Disc can withstand frequent use, fingerprints, scratches and dirt to ensure the storage quality and data security of Blu-ray products.
Technically, the Blu-ray recorder system can be compatible with various optical disc products that appeared before. The huge capacity of Blu-ray products provides the possibility and convenience for high-definition movies, games and large-capacity data storage. It will greatly promote the development of high-definition entertainment. At present, Blu-ray technology has been supported by more than 170 large game companies, film companies, consumer electronics and home computer manufacturers around the world. Seven of the eight major film companies: Disney, Fox, Paramount, Warner, Sony, MGM and Lionsgate.
At present, the popular DVD technology uses a red laser with a wavelength of 650nm and a focusing lens with a digital aperture of 0.6, and the disc thickness is 0.6 mm ... Blue-ray DVD technology uses a blue-violet laser with a wavelength of 450nm, and successfully reduces the focusing spot size to a very small extent through a digital aperture of 0.85 on a wide-angle lens. In addition, the optical transparent protective layer with the thickness of 0. 1mm is adopted in the disc structure of Blu-ray DVD, which reduces the disorder of reading and writing caused by the inclination of the disc during the rotation, makes it easier to read the disc data, and makes it possible to greatly improve the storage density.
The track pitch of Blu-ray DVD is reduced to 0.32μm, which is only half of the current red-ray DVD. The minimum diameter of its recording unit-groove (or chemical phase change unit) is 0. 14μm, which is much smaller than the 0.4μm groove of red-ray DVD. The storage capacity of single-sided single-layer disc of Blu-ray DVD is defined as 23.3GB, 25GB and 27GB, among which the highest storage capacity (27GB) is nearly 6 times that of single-sided single-layer disc of red DVD (4.7GB), which is enough to store high-definition digital video content with playing time exceeding 2 hours or standard TV programs with playing time exceeding 13 hours (VHS quality, 3.8MB/s). This is only a single-sided single-layer capacity. Just like the traditional red DVD, the blue DVD can also be made into single-sided and double-sided double layers. For example, Panasonic and Hitachi have demonstrated a double-layer Blu-ray DVD with a capacity of about 50GB, and strive to write this specification into the technical standard of Blu-ray DVD by the end of 2002.
The proposed Blu-ray DVD format has a data transmission rate of 36MB/s and adopts MPEG-2 as the compression mode of streaming media, so as to be compatible with global digital broadcasting standards. However, the Blu-ray DVD format itself is not compatible with the existing red DVD format, so some sponsors are still actively proposing that the Blu-ray DVD system should be compatible with the traditional DVD in some aspects in order to promote it more smoothly. Whether this measure can be realized is expected to be known in 2003.
The launch of Blu-ray DVD is expected to end the dispute over erasable DVD standards, and its stronger market driving force is likely to be the launch of high-definition digital television (HDTV) services worldwide (for example, the United States will first open the land-based cable network of HDTV in 2003, and China has also established a plan to gradually completely replace the traditional TV network in a few years). In fact, the storage technology of replacing red laser with blue laser band was not developed by the main members of DVD forum, but was patented by Nichia and ToyodaGosai in Japan. According to IDG, the two companies have been arguing and litigating for six years in order to compete for the patent of blue light storage technology, which has delayed the development and application of this technology. However, in mid-August, 2002, the controversy finally settled, and the two manufacturers began to provide technical licenses to other manufacturers through negotiation and cooperation, thus clearing a major obstacle to the development of Blu-ray DVD technology and making manufacturers who had long planned to develop Blu-ray DVD storage systems smile.
phylogeny
1998, Philips and Sony took the lead in publishing the technical papers of the next generation optical disc, and began to develop the technical scheme of realizing 23 GB ~ 25 GB on one side and single layer, which brought a surprise to the industry.
On February 19, 2002, with Sony, Philips and Panasonic as the core, Hitachi, Pioneer, Samsung, LG, Sharp and Thomson * * * jointly released the 0.9 version of Blu-ray Disc (BD for short) technical standard. Blu-ray means Blu-ray, so February 19 officially showed the birth of the next generation DVD candidate-Blu-ray Disc.
BD Group then officially released the BD specification version 1.0 on June 4th, 2002, with a volume of ***3 * * 5000 USD, which indicates that the design of BD has been completely established.
Although there has been controversy about which of BD and HD-DVD will become the next generation Blu-ray storage standard, it has also prompted the two companies to innovate and carry out technological reforms. In 2003, Blu-ray laser heads reached the mass production level, but in 2006, Blu-ray products suitable for the market began to appear.
In 2006, Sony, Pioneer and Samsung all released their own Blu-ray technologies and Blu-ray products, and all put forward their own Blu-ray plans. In the China market, on July 6th, 2006, BenQ took the lead in launching its molded blue light products. It can be said that 2006 is the real "first year of Blu-ray".
On February 16, 2008, a shocking news was reported in the headline news reported by NHK TV in Japan: Toshiba announced that it would abandon the HD-DVD format. According to the news program, Toshiba declared a complete failure in this "next-generation DVD specification war", with losses as high as tens of billions of yen. At the same time, Tokyo Branch of Reuters also published the news that Toshiba abandoned HD-DVD and ended the format war.
From Microsoft, which only supports HD-DVD, to the announcement that it supports both formats at the same time, Warner of HD-DVD camp defected some time ago, and the HD-DVD camp headed by Toshiba became more and more difficult. Today, even Toshiba announced that it would abandon the HD-DVD format. This specification dispute, which lasted for several years, ended in the victory of Blu-ray.
Application of blue light
At the end of 2007, Sony launched the first HD player with Blu-ray DVD in China: BDP-S300/BM Blu-ray Player, which started the commercialization of Blu-ray in China. The impressive achievements of PlayStation3 have laid the foundation for the standard battle between Blu-ray and HD-DVD, but the price of this DVD as high as 5,000 yuan has discouraged many consumers. Due to the cost constraints, the popularity of BlueRay still has a long way to go.
Performance standard of BDP-S300/BM Blu-ray player
7. 1 surround channel
1080 signal output
24 frames per second, like a movie.
X.v. color gamut standard
BRAVIATheatreSync cinema synchronization function
Change and size
The single-layer Blu-ray disc has a capacity of 25 or 22GB, which is enough to burn a high-definition movie for up to 4 hours. The double layer can even reach 46 or 54GB capacity, which is enough to burn a high-definition movie for 8 hours. The capacity of 100 or 200GB is 4 layers and 8 layers respectively. According to the current research, TDK has announced the development of a four-layer optical disc with a capacity of 100GB. Blu-ray disc player uses blue laser to read files on the disc. Because the wavelength of blue light is short, you can read compact discs with high density. So why can Blu-ray read and write more discs? This should start with the laser: the laser for reading and writing is a very accurate light, accurate to the limit, that is, the general wavelength of light. Because the wavelength of red light is 700nm, and the wavelength of blue light is only 400nm, blue laser can actually be more accurate, and it can read and write a point with only 200nm, while red laser can only read and write a point with 350nm, so the information recorded on the same optical disc is natural.
Blu-RayDisk is a Blu-ray disc, which is one of the standards of the next generation DVD. The leaders are Sony and Toshiba, with Sony, Panasonic and Philips as the core, and the support of giants such as Pioneer, Hitachi, Samsung and LG. The storage principle is groove recording, and the traditional groove recording is adopted. And the storage and data management with larger capacity are realized by more advanced jitter addressing, reaching a shocking 100GB. Compared with the traditional storage form of CD or DVD, BD disc obviously brings better reflectivity and storage density, which is the key to its capacity breakthrough.
The diameter of Blu-ray disc is 12cm, which is the same as that of ordinary CD and DVD. This kind of optical disc uses a blue laser of 405nm to emit a single layer of light on one side.
CD-ROM can record and play video data as long as 27GB, which is more than 5 times larger than the existing DVD (the capacity of DVD is generally 4.7GB) and can record 13 hours.
Ordinary TV programs or 2-hour HDTV programs. Blu-ray disc adopts MPEG-2 compression technology.