Optical Disc Lineage: CD, CD-ROM, DVD, Blu-ray and the HD DVD Format War (1979-2008)

Short answer: the CD, DVD and Blu-ray are one 12 cm disc family in which the laser wavelength and track pitch were cut with each generation. The CD was demonstrated in prototype by Philips on 8 March 1979, fixed as a joint Philips and Sony standard in June 1980 and sold from autumn 1982. DVD came out of a split between two rival camps that IBM-led computer companies pushed into one format on 15 September 1995 (final specifications 8 December 1995). Blu-ray was announced on 19 February 2002 around a 405 nm laser, and the HD DVD rival was withdrawn by Toshiba on 19 February 2008, six weeks after Warner Bros. chose Blu-ray exclusively.

Before the CD: video on disc, 1972-1978. Peek's article says Philips presented its Video Long Play (VLP) system to the press in 1972, that VLP reached the market in 1974 and was sold in the United States from 1978 as LaserVision, using a 30 cm disc read by a 1 mW helium-neon laser at 633 nm. Wolpin's history instead credits the LaserDisc to a 3M and Stanford Research Institute partnership introduced by Pioneer and Philips in late 1978, so the sources describe the origin of the video disc in different terms. Peek also records that an analog audio disc (ALP, 1974-1975) was a dead end because dropouts caused audible clicks, which led Philips to digital audio with error correction.

1979-1980: the Philips and Sony standard. Peek writes that the Philips prototype used a disc of 11.5 cm (the diagonal of a compact cassette), 14-bit quantisation and a 44.3 kHz sampling frequency, and was shown to about 300 journalists in Eindhoven on 8 March 1979. Sony agreed to cooperate after the Philips delegation visit of 14 to 23 March 1979. Six joint meetings, from 27 and 28 August 1979 in Eindhoven to 17 and 18 June 1980 in Tokyo, produced CIRC (cross-interleaved Reed-Solomon code) for error correction and EFM (eight-to-fourteen modulation), a 44.1 kHz sampling rate, 16-bit linear quantisation, about 60 minutes of playing time and a 12 cm disc. Peek relays J. Sinjou's account that the move from 11.5 cm to 12 cm was Sony vice chairman N. Ohga's wish so that a 74-minute performance of Beethoven's Ninth could fit; this is a participant anecdote from one author. The Sony history page says the four companies Sony, CBS/Sony, Philips and PolyGram announced the CD system on 31 August 1982 and that Sony launched the CDP-101 on 1 October 1982, and that the CD became the de facto standard after other hardware companies announced they would follow the Sony and Philips standard. The two sources are both company-affiliated.

1983-1986: from audio to data, CD-ROM. MacTech's explanation (Apple developer documentation) says CD-ROM discs are laid out in 2048-byte physical sectors under a standard published by Philips and Sony called the Yellow Book, and that a group of industry representatives met at the High Sierra Hotel and Casino at Lake Tahoe in late 1985 to agree a common file system, producing the High Sierra working paper of 28 May 1986. ECMA-119's brief history says US companies invited experts in October 1985, that the result was a report of May 1986 known as the 'High Sierra Group' proposal, that Ecma issued ECMA-119 in December 1986 and that ISO then produced ISO 9660 by the fast-track procedure; the 2nd edition (adopted 10 December 1987) is technically identical to ISO 9660. Wolpin puts the introduction of CD-ROM in October 1983 and Philips' CD-Interactive in 1987, and describes MPEG-1 VideoCD as the first digital video disc; those three statements come from that single source. The same article quotes Toshiba's Koji Hase on selling CD-ROM against floppy disks and gives the CD-ROM capacity as both 650 and 800 megabytes in different places, so no CD-ROM capacity figure is used here.

1992-1994: two camps for digital video on a disc. Wolpin's account (single detailed source, based on participant interviews) says Toshiba's Koji Hase and Warner Home Video's Warren Lieberfarb began working together in April 1992 on a project code-named Taz, that Philips left that effort in early 1994 to work with Sony, and that Toshiba and Matsushita completed the Super Density (SD) disc: two 0.6 mm halves bonded together, each said to hold 5 GB, with an experimental but more efficient modulation scheme. Sony and Philips proposed a 1.2 mm single disc of 3.75 GB with an enhanced CD modulation called EFM+ (Wolpin). On 16 December 1994 Philips and Sony issued a press release proposing the high-density multimedia CD (MMCD); the SD Alliance answered on 24 January 1995 (both per Wolpin). The movie-studio committee formed by Lieberfarb listed requirements in September 1994, including at least 135 minutes of playing time (Wolpin); the Toshiba statement of December 1995 gives 133 minutes per side at 4.69 Mbit/s average for the final format, which is slightly under that figure, and this card does not reconcile the two.

1995: IBM-led arbitration and the unified format. Wolpin says IBM's Alan Bell chaired a Technical Working Group of computer companies (IBM, Apple, Compaq, Microsoft, later Hewlett-Packard) that issued nine requirements on 3 May 1995 and pressed for one format. The Los Angeles Times of 16 September 1995 independently confirms the central events: the two factions had been fighting for nearly a year, Sony and Philips presented a new proposal the previous month, and after meetings in Honolulu with IBM's evaluators the Toshiba and Time Warner camp accepted a unified format on Friday 15 September 1995. It says the unified format took the disc structure from Toshiba's proposal (two thin discs bonded together) and the modulation system from Sony and Philips, and quotes Bell: 'I wouldn't call it a compromise--it's a unification.' Wolpin adds that the SD camp argued the Sony-Philips modulation would lose more than a quarter of a gigabyte of capacity, that the IBM group judged that loss unimportant, and that final compromise specifications were announced at Comdex on 13 November 1995. The Toshiba statement of 8 December 1995, issued on behalf of Toshiba, Matsushita, Sony, Philips, Time Warner, Pioneer, JVC, Hitachi and Mitsubishi Electric, announces agreement on final details and states the name DVD. Wolpin's story that Toshiba's Nishimuro chose 'versatile' from a dictionary to replace 'video' is a participant recollection from a single source.

The DVD specification as written down. The Toshiba statement lists: 120 mm disc, 1.2 mm thick made of two 0.6 mm discs, 4.7 GB per side, 0.74 micrometre track pitch, laser wavelength 650 nm or 635 nm, numerical aperture 0.6, Reed-Solomon product code error correction, 8-16 signal modulation, MPEG-2 video, Dolby AC-3 audio, and Micro UDF with ISO 9660 as file structures. ECMA-267 (3rd edition, April 2001) confirms 650 nm, NA 0.60, 0.74 micrometre track pitch, 8-to-16 modulation (run length 2 to 10 zeros) and a Reed-Solomon product code of 208 by 182 bytes (outer code RS(208,192,17), inner code RS(182,172,11)), and specifies four disc types: A, one layer, 4.7 GB; B, two single-layer sides, 9.4 GB; C, two layers on one side, 8.5 GB; D, two double-layer sides, 17.0 GB, with 55 micrometre spacer between layers on types C and D. ECMA-267's history says ten companies called the DVD Consortium proposed the work to Ecma TC31 in February 1997. Wolpin dates the first player, the Toshiba SD-3000, to November 1996 in Japan, the first United States players to February 1997 and the first titles to the following month, and says the copy-protection scheme CSS (Content Scrambling System) with six regions was endorsed on 29 October 1996; these dates are from that one source.

The recordable DVD split. ECMA-267's history mentions rewritable DVD-RAM and writable DVD-R work supported by DVD Forum members, and Wolpin (writing in 2007) describes competing recordable DVD decks that could not play each other's discs. This card does not document the DVD-R, DVD-RW, DVD+RW and DVD-RAM dispute in detail because only those two sources were read.

The blue laser, 1996. Laser Focus World reported in April 1996 that Nichia's Shuji Nakamura had shown an InGaN multiple-quantum-well laser emitting at 417 nm at Photonics West in January 1996, operating at room temperature on pulsed current, with a threshold current of 1.7 A, 215 mW pulsed output per facet and operation for up to 24 hours pulsed; continuous-wave operation was still a goal and no lifetime data existed. This is the only source read for this milestone (the paper abstracts that would confirm it were seen only as search excerpts). The Blu-ray Founders white paper states that GaN laser diodes give 'the shortest wavelength of all laser diodes' and that the 405 nm wavelength was chosen with the resistance of the disc plastic in mind; the same document says 'when BD was developed in 1996' there were no cover materials meeting the thickness and birefringence requirements, which is a format-owner statement about the date of the work, not an independently confirmed date.

2002: Blu-ray announced. On 19 February 2002 nine companies (Hitachi, LG, Matsushita, Pioneer, Philips, Samsung, Sharp, Sony and Thomson Multimedia) announced the basic specification for a rewritable video recording disc using a 405 nm blue-violet laser, a lens NA of 0.85 and a 0.1 mm protective layer, with 23.3, 25 or 27 GB on a single layer of 12 cm phase-change disc, a 0.32 micrometre track pitch (about half the DVD pitch, their statement says), a 36 Mbit/s data rate and MPEG-2 transport stream recording; they said they were aiming for more than 30 GB single-layer and more than 50 GB dual-layer capacities (all vendor claims). The August 2004 white paper repeats the optical parameters, lists 46.6, 50 and 54 GB for dual-layer discs, a 17PP modulation code, PRML signal processing (the same read-channel idea covered in the PRML card), a picket-code error correction with 64 KB blocks and 25 micrometre spacing between dual layers. EDN reported in November 2003 that the Blu-ray group had ten founding members and planned BD-ROM version 0.9 for the end of 2003 and version 1.0 in the first quarter of 2004; the 2002 press release names nine, so the count differs between sources.

2003-2006: HD DVD proposed and the two camps ship. EDN (14 November 2003) reports that the DVD Forum's technical working group had approved a high-definition format proposal based on Toshiba and NEC's Advanced Optical Disc (AOD) technology, which kept the bonded-disc structure of the red-laser DVD, with 15 GB for a single-layer ROM disc, 30 GB dual-layer and 20 GB single-layer rewritable, and that the Blu-ray founders, who also sat on the DVD Forum steering committee, voted no or abstained in June, so the steering committee had to vote again. AfterDawn reported on 26 November 2003 that the steering committee adopted the Toshiba and NEC proposal as its draft HD-DVD format, in an 'although as far as we know, not an ultimate decision yet' wording, and quoted 15 to 20 GB per side (the EDN figures are 15 GB ROM and 20 GB rewritable single layer). CNET reported on 18 April 2006 that Toshiba's first HD DVD players were reaching stores that week, about two months before the first Blu-ray player, and that seven studios backed Blu-ray, three backed HD DVD (two of them also Blu-ray) and Universal supported HD DVD exclusively. Computerworld (15 June 2006) reported Samsung's BD-P1000 as the first generally available Blu-ray player in the United States, with shipping later that month, and gave 50 GB for Blu-ray and 30 GB for HD DVD as maximum capacities.

2008: the end of the format war. On 4 January 2008 Warner Bros. announced that it would release its high-definition titles exclusively on Blu-ray beginning later that year, while continuing HD DVD releases until the end of May 2008 after a short window behind standard DVD and Blu-ray releases; its executives said 'a two-format landscape has led to consumer confusion and indifference toward high definition' (vendor statement, quoted from the full release reproduced by Deadline). Reuters, in the NBC News copy, reported the same announcement and said that, at that date, 20th Century Fox, Disney and Lionsgate were among studios backing Blu-ray while Paramount and NBC Universal released movies on HD DVD. On 19 February 2008 Toshiba announced that it would no longer develop, manufacture or market HD DVD players and recorders, would reduce retail shipments aiming for cessation of the business by the end of March 2008, would end volume production of HD DVD drives for PCs and games in the same period, and would keep supporting owners and its DVD Forum membership. Toshiba's president said the company had 'carefully assessed the long-term impact of continuing the so-called next-generation format war and concluded that a swift decision will best help the market develop' (vendor statement).

What the sources do not settle. The origin of the video disc (3M and SRI according to Wolpin, Philips VLP according to Peek); who first proposed the 12 cm CD diameter beyond the Sinjou anecdote; the date of CD-ROM's introduction beyond Wolpin; the capacity of CD-ROM discs (650 or 800 MB in one source); whether the final DVD specifications date from 13 November or 8 December 1995 (Wolpin lists both events; Toshiba's statement calls 8 December the final agreement); the number of Blu-ray founders (nine or ten); how much any single event, including the Warner Bros. decision, caused the end of HD DVD, since the sources read give only the companies' own explanations; and the later history of the formats after 2008, which this card does not cover.