Blu-ray, ahh...quite an interesting name...isn’t it? Blu-ray is an optical disc format of the next generation which was developed to enable recording, rewriting and playback of high-definition video (HD). The main purpose of this format is to store large amounts of data, more than five times the storage capacity of traditional DVDs. The discs developed with Blu-ray format are called Blu-ray disc, shortly BDs . BDs can hold upto 25GB-50GB of data depending upon the number of layers on the disc. Now, you may get confused with this layer-language...Normally all the disc at the moment in use are single layered. But these BDs can be multiple layered.i.e the data can be stored in more than one layer on a single disc. If it is a single layer data upto 25GB can be stored and if it is a double layered disc it can be 50GB. And thats not all. This extra capacity is combined with advanced video and audio codecs to offer the consumers a HD experience.
The current discs such as DVD, DVD±R, DVD±RW, and DVD-RAM rely on a red laser to read and write data where as the new format discussed above uses a blue-violet laser instead which is why it is called Blu-ray. All the Blu-ray products are compatible with CDs and DVDs through the use of a BD/DVD/CD compatible optical pickup unit. The reason why the blue-violet laser is used is because of its shorter wavelength than red laser. The blue-violet laser has a wavelength of 405nm
Where as that of red’s is 650nm. This makes it possible to focus the laser spot with even greater precision which allows more data to be stored in much less space. Hence it beats the professional CDs and DVDs in all their features. I had also learned that the recent development by Pioneer has dramatically increased the storage capacity to 500GB on a single disc by using 20 layers. Hahaha...isn’t it quite amazing?
For more information check out these links Blu-ray movies and Blu-ray reviews.