Blu-Ray set to take the world by storm!

The Blu-ray Disc belongs to a new gen­er­a­tion of opti­cal discs capa­ble of stag­ing high den­sity data. Blu-Ray tech­nol­ogy is based on a blue-violet coloured laser. The blue laser oper­ates at a wave length of 405 nm, while older tech­nol­ogy such as DVDs and CDs are based on red and infrared lasers that works at 650 and 780 nm. Since the wave length is shorter with a blue laser, the new Blu-ray tech­nol­ogy makes is pos­si­ble to store much more information

The advan­tage with the Blu-ray tech­nol­ogy is that the laser beam can be focused much more tightly at the sur­face of the disc. Tight focus means that a smaller spot will be pro­duced on the sur­face on the disc, and when the spots become smaller there will nat­u­rally be room for more infor­ma­tion on each disc. The min­i­mum spot size of any laser depends on a nat­u­rally accru­ing phe­nom­e­non called dif­frac­tion. The nar­row beam of light sent out from a laser will always diverge into a wider beam even­tu­ally, due to the nat­ural dif­frac­tion of waves. Dif­frac­tion will also occur the waves meet an obstruc­tion. By reduc­ing the wave­length of a laser, we can affect the diffraction.

In Blu-ray tech­nol­ogy, the dif­frac­tions is also affected by the fact that the lens used to focus the light has a higher numer­i­cal aper­ture than the lenses found in ordi­nary DVDs — 0.85 instead of 0.6. Blu-ray tech­nol­ogy based appli­ances are also equipped with a dual-lens sys­tem of supreme qual­ity, and the cover layer has been made thin­ner in order to pre­vent unwanted opti­cal effects. All this makes it pos­si­ble for a Blu-ray laser to focus on much smaller spots. The opti­cal improve­ments are accom­pa­nied with a new method for encod­ing data which makes it pos­si­ble to store even more data on the Blu-ray disc.

The stan­dard for Blu-ray tech­nol­ogy has been devel­oped as a joint ven­ture between sev­eral major man­u­fac­tur­ers of PCs and con­sumer elec­tron­ics, includ­ing Sony and Philips. The group is called the Blu-ray Disc Asso­ci­a­tion (BDA). The first Blu-ray recorder was launched in Japan in 2003, by Sony. Today, Sam­sung, JVC, Mat­sushita (Pana­sonic) and LG Elec­tron­ics are all exam­ples of com­pa­nies using Blu-ray tech­nol­ogy in their prod­ucts. Hewlett Packard has announced that they will release desk­top PCs equipped with Blu-ray tech­nol­ogy in late 2005.

The main com­peti­tor for the Blu-ray tech­nol­ogy is the HD DVD for­mat which is also capa­ble of stor­ing more infor­ma­tion than a nor­mal DVD. The Blu-ray tech­nol­ogy does how­ever allow for more infor­ma­tion per layer than the HD DVD for­mat — 25 GB com­pared to 15 GB. The Blu-ray tech­nol­ogy will on the other hand most likely be more expen­sive to sup­port, at least ini­tially, which can make the HD DVD a tempt­ing alter­na­tive. In a Blu-ray disc, the data is stored extremely close to the sur­face. This made the first Blu-ray discs extremely vul­ner­a­ble to scratch­ing and many users pre­ferred the tougher HD DVD discs. Since 2004, all Blu-ray discs are coated with a clear poly­mer called “Dura­bis” which makes them much more durable. Accord­ing to the devel­op­ers of Dura­bis, the TDK Cor­po­ra­tion, a coated Blu-ray disc will work even after being attacked with a screwdriver.

Paul Col­bert of Blu Ray World is an author of var­i­ous arti­cles relat­ing to new tech­nol­ogy and inno­va­tions. All con­tent may be used freely but may not be altered in any­way with­out prior writ­ten con­sent by web­cash­flow LLC and a link back to Blu-Ray-World.com must be given.