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Disc Rot
Disc rot is the tendency of CD, DVD, or other optical discs to become unreadable because of chemical deterioration. The causes include oxidation of the reflective layer, reactions with contaminants, ultra-violet light damage, and de-bonding of the adhesive used to adhere the layers of the disc together. Causes In CDs, the reflective layer is immediately beneath a thin protective layer of lacquer, and is also exposed at the edge of the disc. The lacquer protecting the edge of an optical disc can usually be seen without magnification. It is rarely uniformly thick; thickness variations are usually visible. The reflective layer is typically aluminium, which reacts easily with several commonly encountered chemicals such as oxygen, sulfur, and certain ions carried by liquid water. In ordinary use, a surface layer of aluminium oxide is formed quickly when an aluminium surface is exposed to the atmosphere; it serves as passivation for the bulk aluminium with regard to many, but not all, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compact Disc
The compact disc (CD) is a Digital media, digital optical disc data storage format co-developed by Philips and Sony to store and play digital audio recordings. It employs the Compact Disc Digital Audio (CD-DA) standard and was capable of holding of uncompressed stereo audio. First released in Japan in October 1982, the CD was the second optical disc format to reach the market, following the larger LaserDisc (LD). In later years, the technology was adapted for computer data storage as CD-ROM and subsequently expanded into various writable and multimedia formats. , over 200 billion CDs (including audio CDs, CD-ROMs, and CD-Rs) had been sold worldwide. Standard CDs have a diameter of and typically hold up to 74 minutes of audio or approximately of data. This was later regularly extended to 80 minutes or by reducing the spacing between data tracks, with some discs unofficially reaching up to 99 minutes or which falls outside established specifications. Smaller variants, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVD-D
DVD-Ds, also referred to as disposable DVDs, were a type of disposable digital versatile disc/digital video disc that were designed to be used for a maximum 48 hours after the containing package is opened. After this time, the DVDs became unreadable to DVD players because they contained a chemical that, after the set period of time, will prevent the underlying data from being read by DVD drives. The medium in itself was copy protection neutral and did not require additional digital rights management types of applications to be installed for the content to be accessible. See also * DIVX and Flexplay, two other disposable disc formats * Disc rot, the ''unintended'' decay of optical discs due to physical or chemical deterioration * Planned obsolescence In economics and industrial design, planned obsolescence (also called built-in obsolescence or premature obsolescence) is the concept of policies planning or designing a good (economics), product with an artificially limited Produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Rot
Data degradation is the gradual corruption of computer data due to an accumulation of non-critical failures in a data storage device. It is also referred to as data decay, data rot or bit rot. This results in a decline in data quality over time, even when the data is not being utilized. The concept of data degradation involves progressively minimizing data in interconnected processes, where data is used for multiple purposes at different levels of detail. At specific points in the process chain, data is irreversibly reduced to a level that remains sufficient for the successful completion of the following steps Manifestations Primary storages Data degradation in dynamic random-access memory (DRAM) can occur when the electric charge of a bit in DRAM disperses, possibly altering program code or stored data. DRAM may be altered by cosmic rays or other high-energy particles. Such data degradation is known as a soft error. ECC memory can be used to mitigate this type of data degrad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conservation And Restoration Of Plastic Objects
Conservation and restoration of objects made from plastics is work dedicated to the conservation of objects of historical and personal value made from plastics. When applied to cultural heritage, this activity is generally undertaken by a conservator-restorer. Background Within museum collections, there are a variety of artworks and artifacts that are composed of organic plastic materials, either synthetic or semi-synthetic; these were created for a range of uses from artistic, to technical, to domestic use. Plastics have become an integral component of life, and many plastic artifacts have become cultural icons or objects worth preserving for the future. Although relatively new materials for museum collections, having originated in the 19th century, plastics are deteriorating at an alarming rate. This risks the loss not only of the objects themselves, but other nearby materials may also be degraded by outgassing or reactions with other released chemicals. Identification of plas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terre Haute, Indiana
Terre Haute ( ) is a city in Vigo County, Indiana, United States, and its county seat. As of the 2020 United States census, 2020 census, the city had a population of 58,389 and Terre Haute metropolitan area, its metropolitan area had a population of 168,716. Located along the Wabash River about east of the state border with Illinois, Terre Haute is one of the largest cities in the Wabash Valley and is known as the Queen City of the Wabash. The city is home to multiple higher-education institutions, including Indiana State University, Rose-Hulman Institute of Technology, and Ivy Tech Community College of Indiana. It also contains the United States Penitentiary, Terre Haute, which houses the US federal death row. History Terre Haute's name is derived from the French phrase ''terre haute'' (pronounced in French), meaning "highland". It was named by French-Canadian explorers and fur trappers to the area in the early 18th century to describe the unique location above the Wabash Ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DADC
Sony Digital Audio Disc Corporation (Sony DADC) is a manufacturer of CDs, DVDs, UMDs, and Blu-ray Discs, operating numerous plants worldwide. While primarily serving Sony Music Entertainment-owned record labels, Sony Pictures Home Entertainment, and Sony Interactive Entertainment, it also produces discs for other labels, home entertainment distributors, and video game publishers. History Sony DADC's first plant, located in Terre Haute, IN, opened on May 2, 1983, and produced its first CD, Bruce Springsteen's '' Born in the U.S.A.'', in September 1984. It was the first CD manufacturer in the United States and serves as the company's principal CD manufacturing facility and its research and development center. The plant was initially a subsidiary of CBS/Sony Group, but Sony acquired CBS's stake in October 1985. When Sony bought CBS Records in 1988, it acquired the company's manufacturing facilities, some of which later became part of Sony DADC. These included plants in Pitman, NJ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Misnomer
A misnomer is a name that is incorrectly or unsuitably applied. Misnomers often arise because something was named long before its correct nature was known, or because an earlier form of something has been replaced by a later form to which the name no longer suitably applies. A misnomer may also be a word that is used incorrectly or misleadingly. The word "misnomer" does not mean " misunderstanding" or " popular misconception", and a number of misnomers remain in common usage — which is to say that a word being a misnomer does not necessarily make ''usage'' of the word incorrect. Sources of misnomers * An older name being retained after the thing itself has changed (e.g., tin can, mince meat pie, steamroller, tin foil, clothes iron, digital darkroom). This is essentially a metaphorical extension with the name of the older item standing for anything filling the same role. * Transference of a well-known product brand name into a genericized trademark (e.g., Xerox f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminum Oxide
Aluminium oxide (or aluminium(III) oxide) is a chemical compound of aluminium and oxygen with the chemical formula . It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium oxide. It is commonly called alumina and may also be called aloxide, aloxite, ALOX or alundum in various forms and applications and alumina is refined from bauxite. It occurs naturally in its crystalline polymorphic phase α-Al2O3 as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire,which have an alumina content approaching 100%. Al2O3 is used as feedstock to produce aluminium metal, as an abrasive owing to its hardness, and as a refractory material owing to its high melting point. Natural occurrence Corundum is the most common naturally occurring crystalline form of aluminium oxide. Rubies and sapphires are gem-quality forms of corundum, which owe their characteristic colours to trace impurities. Rubies are given their ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LaserDisc
LaserDisc (LD) is a home video format and the first commercial optical disc storage medium. It was developed by Philips, Pioneer Corporation, Pioneer, and the movie studio MCA Inc., MCA. The format was initially marketed in the United States in 1978 under the name DiscoVision, a brand used by MCA. As Pioneer took a greater role in its development and promotion, the format was rebranded LaserVision. While the LaserDisc brand originally referred specifically to Pioneer's line of players, the term gradually came to be used generically to refer to the format as a whole, making it a genericized trademark. The discs typically have a diameter of , similar in size to the phonograph record. Unlike most later optical disc formats, LaserDisc is not fully Digital data, digital; it stores an analog video signal. Many titles featured Compact Disc Digital Audio, CD-quality digital audio, and LaserDisc was the first home video format to support surround sound. Its 425 to 440 horizontal lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Rot
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radiation. The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow and the optical amplifier patented by Gordon Gould. A laser differs from other sources of light in that it emits light that is ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling uses such as optical communication, laser cutting, and lithography. It also allows a laser beam to stay narrow over great distances (collimation), used in laser pointers, lidar, and free-space optical communication. Lasers can also have high temporal coherence, which permits them to emit light with a very narrow frequency spectrum. Temporal coherence can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
