What Is Blu-ray And How It Works?

By Author: Mehul Kenia
Total Articles: 1
Comment this article

It hit the market with a buzz revolution; the manner in which we looked at the small piece of metal and plastic. Yes we are talking about the blu-ray disc which has redefined the digital storage. Blu-ray which is often misspelled as blue-ray, derives it's name from the blue-violet laser, used to read the disc. The blu-ray format was developed to enable recording, rewriting and playback of high-definition video (HD), as well as storing large amounts of data unimaginable on normal DVD (Digital Versatile Disc).

Blu-ray disc is a creation of Blu-ray Disc Association (BDA) which comprises of world's leading consumer electronics, personal computer and media manufacturers including Apple, Dell, Hitachi, HP, JVC, LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK and Thomson. Sony took the lead in launching the blu-ray disc in 2005. Although the complete launch took almost a year, it was in 2006 that first commercial blu-ray movie title hit the market.

Blu-ray standard was established to hold a standard-length movie in HDTV format, or high-definition television. Such movies are displayed in significantly ...
... higher resolution and therefore they require much more storage space. Although the blu-ray disc is identical to an ordinary DVD or CD, the difference lies in the laser that reads it. Instead of a conventional red laser that is used in CDs and DVDs a blue-violet laser which has a shorter wavelength is used to read a blu-ray disc.

What separates blu-ray from a conventional DVD is it's high storage capacity. Compared to a conventional DVD which stores 4.7 GB (giga bytes) data on a single layer and 8.5 GB on dual layer, a blu-ray disc has a whopping storage capacity of 25 and 50 GB respectively. This however is just the beginning as future blu-ray discs will be able to hold up to 200 GB of data. Blu-ray discs also have a higher data transfer rate of 36 Mbps (megabits per second) compared to a DVD which transfers at 10 Mbps.

How Does It Work

Discs store information in spiral grooves called pits which run from the center to the periphery. The data is accessed when a laser reads the other side of these pits i.e. the ‘bumps.' If a disk contains a large amount of information, the pits are packed closely together and are much smaller. As the pits become smaller the laser needs to become more accurate in its ability to read the data. This is exactly why we can store more mp3 songs in a CD compared to a normal Audio CD.

A blu-ray laser thus has the capacity to read small information than a conventional laser used to read a DVD. Blue lasers have a shorter wavelength (405 nanometers) compared to red lasers (650 nanometers) and the smaller beam has the ability to focus on the pits more accurately. This is due to the shorter wavelength that the blue light has, compared to a red on. A blue-Ray discs can read information recorded in pits as small as 0.15 microns twice as small as the pits on a DVD. Blu-ray has reduced the track pitch from 0.74 microns to 0.32 microns. All these things give it a huge storage space.

Although blu-ray discs have had their fair bit of criticism they without any doubt are technology of the future. It is finding it's use in storing high-definition video, blu-ray players, blu-ray recorder, blu-ray laptops and also in popular gaming platform such as the PlayStation 3(PS 3 games).

Bluray disc is becoming immensely popular because of its storage capacity as compared to the conventional DVD's. It is the technology of the future. The author has vast experience in Blu ray disc technology.