Excerpted from Disc Makers white paper, How to Produce a Flawless Blu-ray: BD basics, from storage space to licensing fees.
DVD has migrated to its long-awaited high-definition format, and Blu-ray Disc (BD) has emerged as the survivor after a protracted format war between BD and HD DVD. But what is a Blu-ray disc, really?
A Blu-ray disc is a high-definition optical disc format with many physical characteristics similar to DVD, but with unique differences that set the two formats apart.
The most obvious difference is Blu-ray’s gigantic storage space. Blu-ray disc media come in two sizes: BD-25 (25 GB) and BD-50 (50 GB). Compared to the 4.7 or 8.5 gigabyte storage space of DVD, Blu-Ray discs allows you to store much more data on one disc.
The name Blu-ray refers to the laser used to read the disc. A BD uses a shorter wavelength (blue) laser as opposed to the red laser used for DVDs and CDs. Because of the smaller size of the blue laser, BD utilizes smaller pits and lands than are used on DVDs. Pits and lands are the method by which information is stored on an optical disc. Because the pits and lands are smaller, they can be placed closer together resulting in more information being stored on a disc of the same size.
The Blu-ray format can contain any type of computer data as well as high-definition audio and video. BDs feature an improved disc coating with increased resistance to scratches and smudges, helping to keep data safe and secure from damage. They can be stored in a wide range of environments and temperatures ranging from 4° to 122° Fahrenheit, but it’s advisable to store them in a cool dry place, avoiding temperature extremes. If the discs are stored in an environment different from the operating environment, the discs should be placed in the operating environment for at least two hours before use.
BD discs are quite stable, and some aging tests show the lifespan of replicated discs will last 50-300 years and duplicated BD-Rs can last 20-250 years (10 years before recording). As with any type of blank media, the lifespan of a BD-R is subject to the type of dye and the quality of manufacturing. To ensure the longest lifespan, make sure you purchase the highest quality discs.
Disc Makers white paper,How to Produce a Flawless Blu-ray: BD basics, from storage space to licensing fees, was excerpted from The Fast Path to Blu-ray by Bruce Nazarian, AKA “The Digital Guy.” Bruce is CEO of Digital Media Consulting Group, President of the IDMA, and member of the DVD Association’s National Board of Directors.
Download Disc Makers’ white paper, How to Produce a Flawless Blu-ray: BD basics, from storage space to licensing fees.