History
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The first recorded historical use of an optical disc was in 1884 when Alexander Graham Bell, Chichester Bell and Charles Sumner Tainter recorded sound on a glass disc using a beam of light.
Optophonie is a very early (1931) example of a recording device using light for both recording and playing back sound signals on a transparent photograph.
An early optical disc system existed in 1935, named Lichttonorgel.citation needed
An early analog optical disc used for video recording was invented by David Paul Gregg in 1958 and patented in the US in 1961 and 1969. This form of optical disc was a very early form of the DVD (U.S. Patent 3,430,966 ). It is of special interest that U.S. Patent 4,893,297 , filed 1989, issued 1990, generated royalty income for Pioneer Corporation's DVA until 2007 —then encompassing the CD, DVD, and Blu-ray systems. In the early 1960s, the Music Corporation of America bought Gregg's patents and his company, Gauss Electrophysics.
American inventor James T. Russell has been credited with inventing the first system to record a digital signal on an optical transparent foil that is lit from behind by a high-power halogen lamp. Russell's patent application was first filed in 1966 and he was granted a patent in 1970. Following litigation, Sony and Philips licensed Russell's patents (then held by a Canadian company, Optical Recording Corp.) in the 1980s.
Both Gregg's and Russell's disc are floppy media read in transparent mode, which imposes serious drawbacks. In the Netherlands in 1969, Philips Research physicist, Pieter Kramer invented an optical videodisc in reflective mode with a protective layer read by a focused laser beam U.S. Patent 5,068,846 , filed 1972, issued 1991. Kramer's physical format is used in all optical discs. In 1975, Philips and MCA began to work together, and in 1978, commercially much too late, they presented their long-awaited Laserdisc in Atlanta. MCA delivered the discs and Philips the players. However, the presentation was a commercial failure, and the cooperation ended.
In Japan and the U.S., Pioneer succeeded with the Laserdisc until the advent of the DVD. In 1979, Philips and Sony, in consortium, successfully developed the audio compact disc.
In 1979, Exxon STAR Systems in Pasadena, CA built a computer controlled WORM drive that utilized thin film coatings of Tellurium and Selenium on a 12" diameter glass disk. The recording system utilized blue light at 457nm to record and red light at 632.8nm to read. STAR Systems was bought by Storage Technology Corporation (STC) in 1981 and moved to Boulder, CO. Development of the WORM technology was continued using 14" diameter aluminum substrates. Beta testing of the disk drives, originally labeled the Laser Storage Drive 2000 (LSD-2000), was only moderately successful. Many of the disks were shipped to RCA Laboratories (now David Sarnoff Research Center) to be used in the Library of Congress archiving efforts. The STC disks utilized a sealed cartridge with an optical window for protection U.S. Patent 4,542,495 .
The CD-ROM format was developed by Sony and Philips, introduced in 1984, as an extension of Compact Disc Digital Audio and adapted to hold any form of digital data. The same year, Sony demonstrated a LaserDisc data storage format, with a larger data capacity of 3.28 GB.
In the late 1980s and early 1990s, Optex, Inc. of Rockville, MD, built an erasable optical digital video disc system U.S. Patent 5,113,387 using Electron Trapping Optical Media (ETOM)U.S. Patent 5,128,849 . Although this technology was written up in Video Pro Magazine's December 1994 issue promising "the death of the tape", it was never marketed.
In the mid-1990s, a consortium of manufacturers (Sony, Philips, Toshiba, Panasonic) developed the second generation of the optical disc, the DVD.
Magnetic disks found limited applications in storing the data in large amount. So, there was the need of finding some more data storing techniques. As a result, it was found that by using optical means large data storing devices can be made that in turn gave rise to the optical discs. The very first application of this kind was the Compact Disc (CD), which was used in audio systems.
Sony and Philips developed the first generation of the CDs in the mid-1980s with the complete specifications for these devices. With the help of this kind of technology the possibility of representing the analog signal into digital signal was exploited to a great level. For this purpose, the 16-bit samples of the analog signal were taken at the rate of 44,100 samples per second. This sample rate was based on the Nyquist rate of 40,000 samples per second required to capture the audible frequency range to 20 kHz without aliasing, with an additional tolerance to allow the use of less-than-perfect analog audio pre-filters to remove any higher frequencies. The first version of the standard allowed up to 75 minutes of music, which required 650MB of storage.
The DVD disc appeared after the CD-ROM had become widespread in society.
The third generation optical disc was developed in 2000–2006 and was introduced as Blu-ray Disc. First movies on Blu-ray Discs were released in June 2006. Blu-ray eventually prevailed in a high definition optical disc format war over a competing format, the HD DVD. A standard Blu-ray disc can hold about 25 GB of data, a DVD about 4.7 GB, and a CD about 700 MB.
First-generationedit
Initially, optical discs were used to store broadcast-quality analog video, and later digital media such as music or computer software. The LaserDisc format stored analog video signals for the distribution of home video, but commercially lost to the VHS videocassette format, due mainly to its high cost and non-re-recordability; other first-generation disc formats were designed only to store digital data and were not initially capable of use as a digital video medium.
Most first-generation disc devices had an infrared laser reading head. The minimum size of the laser spot is proportional to the wavelength of the laser, so wavelength is a limiting factor upon the amount of information that can be stored in a given physical area on the disc. The infrared range is beyond the long-wavelength end of the visible light spectrum, so it supports less density than shorter-wavelength visible light. One example of high-density data storage capacity, achieved with an infrared laser, is 700 MB of net user data for a 12 cm compact disc.
Other factors that affect data storage density include: the existence of multiple layers of data on the disc, the method of rotation (Constant linear velocity (CLV), Constant angular velocity (CAV), or zoned-CAV), the composition of lands and pits, and how much margin is unused is at the center and the edge of the disc.
- Compact disc (CD) and derivatives
- Audio CD
- Video CD (VCD)
- Super Video CD
- CD Video
- LaserDisc
- GD-ROM
- Phase-change Dual
- Double Density Compact Disc (DDCD)
- Magneto-optical disc
- MiniDisc
- Write Once Read Many (WORM)
Second-generationedit
Second-generation optical discs were for storing great amounts of data, including broadcast-quality digital video. Such discs usually are read with a visible-light laser (usually red); the shorter wavelength and greater numerical aperture allow a narrower light beam, permitting smaller pits and lands in the disc. In the DVD format, this allows 4.7 GB storage on a standard 12 cm, single-sided, single-layer disc; alternatively, smaller media, such as the DataPlay format, can have capacity comparable to that of the larger, standard compact 12 cm disc.
- DVD and derivatives
- DVD-Audio
- DualDisc
- Digital Video Express (DIVX)
- DVD-RAM
- Nintendo GameCube Game Disc (miniDVD derivative)
- Wii Optical Disc (DVD derivative)
- Super Audio CD
- Enhanced Versatile Disc
- DataPlay
- Universal Media Disc
- Ultra Density Optical
Third-generationedit
Third-generation optical discs are used for distributing high-definition video and videogames and support greater data storage capacities, accomplished with short-wavelength visible-light lasers and greater numerical apertures. Blu-ray Disc and HD DVD uses blue-violet lasers and focusing optics of greater aperture, for use with discs with smaller pits and lands, thereby greater data storage capacity per layer. In practice, the effective multimedia presentation capacity is improved with enhanced video data compression codecs such as H.264/MPEG-4 AVC and VC-1.
- Blu-ray (up to 400 GB - experimental)
- Wii U Optical Disc (25 GB per layer)
- HD DVD (discontinued disc format, up to 51 GB triple layer)
- CBHD (a derivative of the HD DVD format)
- HD VMD
- Professional Disc
Announced but not released:
- Digital Multilayer Disk
- Fluorescent Multilayer Disc
- Forward Versatile Disc
Fourth-generationedit
The following formats go beyond the current third-generation discs and have the potential to hold more than one terabyte (1 TB) of data and at least some are meant for cold data storage in data centers:dubious
- Archival Disc
- Holographic Versatile Disc
- Ultra HD Bluray
Announced but not released:
- LS-R
- Protein-coated disc
- Stacked Volumetric Optical Disc
- 5D DVD
- 3D optical data storage (not a single technology, examples are Hyper CD-ROM and Fluorescent Multilayer Disc)
Overview of optical typesedit
Name | Capacity | ExperimentalNote | YearsNote |
---|---|---|---|
LaserDisc (LD) | 0.3 GB | 1971–2001 | |
Write Once Read Many Disk (WORM) | 0.2–6.0 GB | 1979–1984 | |
Compact Disc (CD) | 0.7–0.9 GB | 1982–today | |
Electron Trapping Optical Memory (ETOM) | 6.0–12.0 GB | 1987–1996 | |
MiniDisc (MD) | 0.14–1.0 GB | 1989–today | |
Magneto Optical Disc (MOD) | 0.1–16.7 GB | 1990–present | |
Digital Versatile Disc (DVD) | 4.7–17 GB | 1995–present | |
LIMDOW (Laser Intensity Modulation Direct OverWrite) | 2.6 GB | 10 GB | 1996–present |
GD-ROM | 1.2 GB | 1997–present | |
Fluorescent Multilayer Disc | 50–140 GB | 1998-2003 | |
Versatile Multilayer Disc (VMD) | 5–20 GB | 100 GB | 1999-2010 |
Hyper CD-ROM | 1 PB | 100 EB | 1999?-? |
DataPlay | 500 MB | 1999-2006 | |
Ultra Density Optical (UDO) | 30–60 GB | 2000-present | |
FVD (FVD) | 5.4–15 GB | 2001-present | |
Enhanced Versatile Disc (EVD) | DVD | 2002-2004 | |
HD DVD | 15–51 GB | 1 TBcitation needed | 2002-2008 |
Blu-ray Disc (BD) | 25 GB 50 GB 100GB (BDXL) 128 GB (BDXL) |
1 TB | 2002-present 2010-present (BDXL) |
Professional Disc for Data (PDD) | 23 GB | 2003-2006 | |
Professional Disc | 23–128 GB | 2003–present | |
Digital Multilayer Disk | 22-32 GB | 2004–2007 | |
Multiplexed Optical Data Storage (MODS-Disc) | 250 GB–1 TB | 2004–present | |
Universal Media Disc (UMD) | 0.9–1.8 GB | 2004–2014 | |
Holographic Versatile Disc (HVD) | 6.0 TB | 2004–2012 | |
Protein-coated disc | (PCD)50 TB | 2005–2006 | |
M-DISC | 4.7 GB (DVD format) 25 GB (Blu-ray format) 50 GB (Blu-ray format) 100 GB (BDXL format) |
2009–present | |
Archival Disc | 0.3-1 TB | 2014–present | |
Ultra HD Blu-ray | 50 GB 66 GB 100 GB |
2015–present |
- Notes
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