It's an amazing story, with many major battles thrown in for good measure, a narrative that may be definitely worth reading regardless if you're no tech junkie.
To be able to truly understand Blu-ray, you possess to return to the first 80's when CDs or Compact Discs were introduced. CDs were a giant leap forward if you compared it to the current media at that time; primarily because the CD offered more storage, better sound quality and quickly took over as the universal standard for pre-recorded, recordable and rewritable media. CDs had around 650MB of storage capacity which has been revolutionary at that time for data storage and retrieval.
However, no technology stands still, especially when considering our insatiable necessity for more compact storage and better quality images. Hence, we had the roll-out of the DVD in the 90's that have a 5-10 X improvement in capacity above the CD. The DVD allowed for top quality, standard definition video distribution and recording, let alone accommodating larger data application. Another key element to this very seamless transition, was that this DVD spec used the identical factor because the CD which allowed for full backwards compatibility. These key factors would not really lost on the development over the following generation media; this being the Blu-ray Disc.
The beginnings from the Blu-ray were only available in the mid '90's with the development of HDTV sets. Consumers soon realized there seemed to be no media competent at recording or playing back Hd
content. There are no mediums that can store HD codecs, excluding JVCs Digital VHS and Sony's HDCAM; but nothing practical such as the CD and DVD media.
However, it absolutely was known that using lasers with shorter wavelengths you could create optical storage with higher density. With this knowledge, Shuji Nakamura invented practical blue laser diodes. Its commercial use was delayed by the patent lawsuit, but eventually the Blu-ray disc became available and the next thing in the evolution of storage media began.
The Visible Difference: The many benefits of Blu-ray Discs versus DVDs.
Although blu-ray disc are identical physical size of a DVD or CD, they are designed for storing and reading a great deal more data. The true reason for this is certainly its consumption of a blue laser instead of the red laser made use of by DVDs and CDs. The blue laser carries a shorter wavelength, a smaller aperture lens and also a thinner cover layer around the disc that assists you to build a smaller beam spot size capable
of storing and reading a lot more data around the disc.
Not surprisingly, no discussion would be complete without mentioning the actual heated battle involving the two opposing technologies: Blu-ray vs HD-DVD. Each disc format have major backers, behind Blu-ray stands Sony, Dell, Hitachi, Hewlett-Packard, Panasonic, Pioneer, Philips, Samsung... and backing HD-DVD we now have Toshiba, NEC and many major movie studios Universal Studios, Paramount Pictures, Warner Bros and New Line Cinema.
While many believe Blu-ray has won the battle and definately will probably end up being the dominant hi-def technology. (Beta anyone?) The primary argument being storage area, since Blu-ray offers 25 GB for single-layer and 50 GB for dual-layer; this is certainly in comparison with HD-DVD which provides 15 GB for single-layer and 30 GB for dual-layer.