The Blu-ray format is the most promising technology for recording data to optical media. It has a number of significant advantages that have allowed Blu-ray discs to take the leading position in the core segment of the market, displacing competitors.
First generation optical media
A significant leap in the development of data carriers was the so-called optical media, better known as compact discs, which almost completely replaced magnetic floppy disks. Conceptually, they were an improved version of vinyl records familiar from childhood, only instead of sound tracks, zeros and ones were recorded on them, which were read not with a needle, but with a thin laser beam. Due to the fact that the laser beam is much thinner than the needle, it became possible to record up to six hundred megabytes of data on one 12-centimeter disk. Compact discs were the first generation of optical media. Later, devices for self-recording of data on such discs and CDs themselves with the possibility of rewriting went on sale.
The second generation DVD had a denser surface structure than CDs. The possibility of more productive use of the disk area appeared due to the fact that a laser beam generator with a shorter wavelength, that is, thinner, was designed. As a result, much more information could be recorded on a disc of the same area. Even a single-layer DVD could hold about 4.5 gigabytes of data, and the invention of multilayer double-sided discs made it possible to record up to 16 gigabytes on one disc.
The next stage in the development of optical media was the HD DVD format, that is, high-definition DVD. Unlike previous types of media, when recording and reading HD DVD, not a red, but a violet laser was used, the wavelength of which was even shorter, so about 15 gigabytes of data were recorded on a single-layer 12-centimeter disc.
Benefits of Blu-ray
Like HD DVD, Blu-Ray is the third generation of optical media. It was developed by companies competing with HD DVD makers. In the case of Blu-Ray, the same blue-violet laser was used as in HD DVD devices, but the significant difference was in the disc itself. All three generations of optical media consisted of a polycarbonate base, on which a special layer was applied, which served for recording and storing data. This layer was not resistant to mechanical damage, which often led to damage to discs due to scratches or dirt. In 2004, a fundamentally new type of polymer coating was invented, which protected Blu-Ray discs from mechanical stress, making them much stronger and more durable. In addition, this made it possible to reduce the thickness of the protective layer six times, which, in turn, made it possible to write about 25 gigabytes on one disc.
These innovations led to the fact that almost all film companies switched to the Blu-Ray format by 2008, and the HD DVD maker refused to develop the technology in order to avoid the "format war". In addition to everything in the Blu-Ray format, more advanced technologies were used to protect against illegal copying, which, of course, became an additional argument for the main consumers of such media - film companies.
