BluRay Disc Information
Blu-ray or BD, is an optical disc format which enables recording, rewriting and playback of high-definition video, and storing large amounts of data. Blu-ray provides more than 5X the capacity of a DVD with 25GB on a single-layer disc and 50GB on a dual-layer disc. This large capacity with advanced video and audio codecs an amazing HD capabilities. Current optical disc formats such as DVD, DVD±R, DVD±RW, and DVD-RAM use a red laser to read and write data, Blu-ray disk uses a blue-violet laser instead this why its named Blu-ray. Blu-ray disks can be made backwards compatible with CDs and DVDs with the use of a BD/DVD/CD optical pickup unit found in all Blu-ray players today. A blue-violet laser has a shorter wavelength than a red laser, this makes it able to focus the laser with greater precision. Together with the change of numerical aperture is what allows data to be written more tightly and in less space, this is why Blu-ray disks fit more data even though they are the same size as a CD/DVD.
BD-Rs can be written to once, BD-REs can be erased and re-recorded multiple times. The current maximum recording speed for Blu-ray Discs is 12X. Higher recording speeds cause too much shaking for disc to read properly, unlike the much higher maximum speeds of CDs and DVDs.
BR25 disks are single layer write-once with a 25GB maximum capacity.
BR50 disks are dual layer write-once with a 50GB maximum capacity.
The BDXL format supports 100GB and 128GB write-once discs and 100GB re-writable discs for commercial applications.
BDXL is a multi-layered disk recordable in the Blu-ray disk audio video format.
BDXL-RE is a multi-layered disk rewritable in the Blu-ray disk audio video format.