Because now only can guess, what will happen with Blue-Ray and HD-DVD disc and devices I will shortly introduce you their main parameters and advantages.

At this moment with absolutely certainty we can say that the physical dimensions of new discs will be the same as the current known CD and DVD disc. The main difference is in the smaller wavelength of the laser which is used to read and write data on the disc.

By specifications, in Blue-Ray and HD-DVD disc is used laser, who emits light with wavelength of 405 nm (blue-violet color). For example, by specification all DVD devices use 650 nm (red color) wavelength to read and write information on discs. No doubt, this difference of wavelengths mean larger capacity of Blue-Ray and HD-DVD disc.

The thickness of each standard optical disc is 1.2 mm (CD, DVD). It could be summarized that there are 3 layers in the disc. Transparent layer (bottom site of the disc – protection layer), middle layer (in which you can look like in a mirror) and top layer (where you can place your labels). In standard DVD disc, the middle layer (the mirror) is positioned on 0.6 mm deep from the bottom layer. In Blue-Ray disc the middle layer is moved closer to protection layer – on 0.1 mm from the surface. Many people say that the Blue-Ray optical disc is more sensitive to incidentally scratch of protection layer than any other optical disc. Except that, people think that the laser will be positioned very hardly to read the data. In new Blue-Ray players the laser is positioned closer to the disc surface, which treats like risk for scratch. At the end this problem was solved with TDK and their new protection layer. The company specialists think that this new technology give to disc better protection from today’s DVDs.

In HD-DVD disc the middle layer is positioned on 0.6 mm from down surface (protection layer), the same structure like DVD disc. That means that new players for HD-DVD can be vice-versa compatible with current DVD discs.

By capacity factor of Blue-Ray disc will be offered in three variants: BD-ROM, BD-R and BD-RE. Each of the discs will have two different types – single layer (23.3, 25 and 27 GB) and double layer (46.6, 50 and 54 GB). Except this, by specification the technology will offer multi layered discs, the largest of which will be 100-200 GB (for four and eight layers). For owners of digital cameras will be available 8 cm discs with 15Gb capacity.

Like Blue-Ray, the HD-DVD disc will be offered in three main variants also : HD-DVD-ROM, HD-DVD-R and HD-DVD-RW. The capacity of HD-DVD disc will be smaller than Blue-Ray disc. For single layer disc – 15GB and 30 GB for double layer disc. Pity, but multi layered disc will not be available.

The founder of Blue-Ray technology is Sony Corp. Sony says that main target of the company is to lay standard among the film companies. Till now, Sony gained Walt Disney Pictures, Metro-Goldwyn-Mayer, Entertainment, Sony Pictures Entertainment, 20-th Century Fox, Warner Bros, etc. The list includes also other companies – leading PC providers as Hewlett-Packard, Apple Computer, Dell, LG, etc. Microsoft say that they will not develop the Blue-Ray technology with these companies and will not join the alliance.

HD-DVD founders are Toshiba and NEC. They say that will invest in HD-DVD devices. Movie producing companies like Warner Bros, New Line Cinema, Universal Studios and Paramount Pictures also support and joined Toshiba’s and NEC’s concern. Giants like Microsoft and Intel work together for advancing the HD-DVD standard.

Only the time will show which technology will win larger market share. Don’t forget that the destiny of one or other technology depends mostly on the end user mood.

Despite the physical dimensions of Blu – Ray and DVD are identical, is the biggest difference between themof storage capacity. While a 4.7GB DVD in a single layer 8.5 and kept in a double layer, a Blu – ray Disc (BD) has a capacity of 25 GB can be stored in a single layer 50 GB and almost double layer disc. This represents a dramatic increase in storage capacity of up to five times in Blu – ray. Technically speaking, as the name suggests, the Blu – ray Disc is dependent on blue laser – violet with a wavelength of 405 nm, stick in the DVD red laser a wavelength of 650 nm. The shorter wavelength in Blu – Ray allows you to compress data in a very little disk space, and also highlighted at a better quality of reproducibility in both size and performance.

About the experience, Blu – ray discs offer the highest video resolution with a pixel matrix of up to 1920×1080, the 720×576-only DVD. Therefore, the difference in high-definition movies between a> Blu – ray Disc (BD) and a DVD is quite obvious from the pixel area of the two formats. In addition, the video bit rate is as fast as 40 Mbps in a Blu – ray Disc, while it is around 9.8 Mbps on a DVD. Furthermore, the transmission rate in a Blu – ray Disc is between 36 Mbit / s for simple files and 54 Mb / s for audio or video file.

The video format Blu – ray Disc is compatible with MPEG-4 AVC and VC-1, plus support SMPTCMPEG-2 is usually associated with DVDs. In the case of audio, Blu – ray supports all formats, Linear PCM, Dolby Digital, Dolby Digital Plus, Dolby TrueHD, DTS Digital Surround, DTS-HD DVD, as opposed to only Linear PCM, Dolby Digital and DTS Digital Sound surround support. However, it depends on the compatibility of the use of players and recorders. Backward compatibility is also possible and depends primarily on the players and content.

Blu – ray Disc (BD)reading is only available in formats (BD-ROM), recordable (BD-R) and rewritable (BD-RW), like any other DVD or CD. The Blu – Ray read-only format could be used for disseminating high-definition (HD), movies, games and other software first. The other two recordable and rewritable formats can be used to record high (definition HD) and data storage are used. The Blu – ray come with a hard coating.

Apparently there is a big differencebetween a Blu – ray Disc (BD) and a DVD. The Blu – Ray is a far more sophisticated optical disks, with much more space. And now everyone, including the displacement of the leading companies in film studies, music and video recording media, games, etc. refers to the Blu – ray technology for its unparalleled quality high definition (HD) video and audio as well.