Blu-ray
digital optical disc data storage format
Blu-ray (Blu-ray Disc or BD) is a digital optical disc data storage format designed to supersede the DVD format. It was invented and developed in the early-mid 2000s and released worldwide on June 20, 2006, capable of storing several hours of high-definition video (HDTV 720p and 1080p). The main application of Blu-ray is as a medium for video material such as feature films and for the physical distribution of video games for the PlayStation 3, PlayStation 4, PlayStation 5, Xbox One, and Xbox Series X. The name refers to the blue laser used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs, resulting in an increased capacity.
The polycarbonate disc is 12 centimetres (4+3⁄4 inches) in diameter and 1.2 millimetres (1⁄16 inch) thick, the same size as DVDs and CDs. Conventional (or "pre-BDXL") Blu-ray discs contain 25 GB per layer, with dual-layer discs (50 GB) being the industry standard for feature-length video discs. Triple-layer discs (100 GB) and quadruple-layer discs (128 GB) are available for BDXL re-writer drives.
While the DVD-Video specification has a maximum resolution of 480p (NTSC, 720 × 480 pixels) or 576p (PAL, 720 × 576 pixels), the initial specification for storing movies on Blu-ray discs defined a maximum resolution of 1080p (1920 × 1080 pixels) at up to 24 progressive or 29.97 interlaced frames per second. Revisions to the specification allowed newer Blu-ray players to support videos with a resolution of 1440 × 1080 pixels, with Ultra HD Blu-ray players extending the maximum resolution to 4K (3840 × 2160 pixels) and progressive frame rates up to 60 frames per second. Aside from an 8K resolution (7680 × 4320 pixels) Blu-ray format exclusive to Japan, videos with non-standard resolutions must use letterboxing to conform to a resolution supported by the Blu-ray specification. Besides these hardware specifications, Blu-ray is associated with a set of multimedia formats.
This brief starts where responsible research should: with the source description of “Blu-ray” as digital optical disc data storage format. Everything that follows is an evidence route, not borrowed authority.
Why this record matters
The subject matters to the general reference register because the source frames it as digital optical disc data storage format. Its deeper value depends on whether names, dates, institutions and citations support that framing.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 6, 2026. The linked authority identifier is Q47770. The Library of Congress control number is sh2010007700. 2 of 3 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank. The first chronological checks are 2006, 1920, 1080 and 1440.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “Blu-ray” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.