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Blu-ray

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A Blu-ray Disc, often called a BD, is a high-capacity digital optical disc storage format. It was designed to replace the older DVD format by providing much higher data density. This allows the disc to store high-definition video, such as 720p and 1080p resolutions. Today, Blu-ray is a primary medium for feature films and video games. It is used by major gaming consoles, including the PlayStation 3, PlayStation 4, PlayStation 5, Xbox One, and Xbox Series X.

BluRayDiscBack b
BluRayDiscBack b

The technology relies on a blue laser to read data from the disc. This is the namesake of the format. While DVDs use a red laser with a longer wavelength, Blu-ray uses a blue laser operating at 405 nanometers. This shorter wavelength allows the laser to focus on much smaller spots. Because the laser can focus so tightly, information can be stored at a much higher density.

Comparison disk storage
Comparison disk storage

The physical disc is made of polycarbonate plastic. It has the same diameter and thickness as a standard CD or DVD. To protect the data, the recording layer sits under a protective layer. This layer is placed on top of the polycarbonate substrate, whereas DVD layers are often on both sides.

Blu-ray discs come in several different capacities depending on their layers. A standard single-layer disc holds 25GB of data. The industry standard for feature-length movies is the dual-layer disc, which holds 50GB. For users with BDXL re-writer drives, even larger capacities are available. These include triple-layer discs holding 100GB and quadruple-layer discs holding 128GB.

Sony BD-R XL 128GB
Sony BD-R XL 128GB

Engineers have even experimented with much higher capacities. For example, TDK created an experimental disc capable of holding 200GB of data on a single side using six 33GB layers.

Blu-ray 200GB
Blu-ray 200GB

The development of Blu-ray was a long process involving many companies. Sony unveiled the first prototypes in October 2000. The first prototype player was released in Japan in April 2003. However, these early players lacked a standard for pre-recorded movies. Hollywood studios required digital rights management, or DRM, to prevent unauthorized copying. This led to the creation of the Advanced Access Content System, known as AACS. The Blu-ray Disc Association (BDA) was formed to manage the format's development.

schouhamerimmink
schouhamerimmink

When Blu-ray was released worldwide on June 20, 2006, it entered a period known as the high-definition optical disc war. It competed directly against the HD DVD format. HD DVD had a head start in the market, and early Blu-ray sales were slow. However, the format gained massive support through the Sony PlayStation 3 console. Major film studios also began choosing Blu-ray over HD DVD. By January 2007, Blu-ray discs were outselling HD DVDs. In 2008, Warner Bros. announced it would release movies only on Blu-ray. This caused a chain reaction where retailers like Walmart and Best Buy dropped HD DVD. Toshiba eventually discontinued HD DVD in February 2008, leaving Blu-ray as the industry standard.

Video quality on Blu-ray has continued to evolve through various specifications. The initial specification supported a maximum resolution of 1080p. It allowed for up to 24 progressive or 29.97 interlaced frames per second. Newer revisions allowed players to support even higher resolutions. Ultra HD Blu-ray players can now play 4K resolution at up to 60 frames per second.

4K Blu Ray early Best Buy release
4K Blu Ray early Best Buy release

There is even an 8K resolution format, though it is exclusive to Japan. If a video uses a non-standard resolution, it must use letterboxing to fit the supported specifications.

To ensure the discs remain functional, manufacturers developed special coatings. Because the blue laser requires a very thin layer for high density, the discs are sensitive to damage. In 2005, TDK announced a thin, ultra-hard polymer coating called Durabis. This coating protects the bare discs from scratches and damage. This advancement meant that bulky protective cartridges were no longer necessary for consumers.

Comparison CD DVD HDDVD BD
Comparison CD DVD HDDVD BD

This technology ensures that the high-density data remains safe during everyday use. The success of Blu-ray connects various industries, from movie production and gaming to consumer electronics and data storage.

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🖼️ Images & Media (12)
File:BluRayDiscBack b.jpg
BluRayDiscBack b.jpg
File:schouhamerimmink.jpg
schouhamerimmink.jpg
File:Blu-ray 200GB.png
Blu-ray 200GB.png
File:4K Blu Ray early Best Buy release.jpg
4K Blu Ray early Best Buy release.jpg
File:Comparison disk storage.svg
Comparison disk storage.svg
File:Comparison CD DVD HDDVD BD.svg
Comparison CD DVD HDDVD BD.svg
File:Blu-ray keep case.jpg
Blu-ray keep case.jpg
File:Sony BD-R XL 128GB.jpg
Sony BD-R XL 128GB.jpg
File:Blu-ray-regions with key.svg
Blu-ray-regions with key.svg
File:AACS dataflow.svg
AACS dataflow.svg
File:Panasonic DMP-BD60 Blu-Ray Player.jpg
Panasonic DMP-BD60 Blu-Ray Player.jpg
File:Blu ray 3d (logo).svg
Blu ray 3d (logo).svg
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