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| {{Redirect|Looking glass||Looking Glass (disambiguation)}}
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| {{About|wave reflectors (mainly, specular reflection of visible light)}}
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| {{pp-move-indef}}
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| [[Image:Mirror.jpg|frame|right|Mirror reflecting a [[vase]]]] | |
| [[File:Enhanced aluminum coated first surface mirror on an optical flat.JPG|thumb|300px|A [[first surface mirror]] coated with aluminum and enhanced with dielectric coatings. The mirror was constructed from an [[optical flat]] with a flatness of <math>\lambda</math>/20, which equates to a surface deviation less than 31.6 nanometers.]]
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| A '''mirror''' is an object that [[Reflection (physics)|reflects]] light in a way that preserves much of its original quality subsequent to its contact with the mirror.
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| Some mirrors also filter out some wavelengths, while preserving other wavelengths in the reflection. This is different from other light-reflecting objects that do not preserve much of the original wave signal other than color and diffuse reflected light. The most familiar type of mirror is the [[plane mirror]], which has a flat surface. [[Curved mirror]]s are also used, to produce [[magnification|magnified]] or diminished images or focus light or simply distort the reflected image.
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| Mirrors are commonly used for [[personal grooming]] or admiring oneself (in which case the [[Archaism|archaic term]] '''looking-glass''' is sometimes still used), decoration, and architecture. Mirrors are also used in scientific apparatus such as [[telescope]]s and [[laser]]s, cameras, and industrial machinery. Most mirrors are designed for [[visible light]]; however, mirrors designed for other types of waves or other [[wavelength]]s of [[electromagnetic radiation]] are also used, especially in non-optical [[#Instruments|instruments]].
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| ==History==
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| [[File:NAMA Femme au miroir.jpg|thumb|Seated woman holding a mirror.[[Ancient Greece|Ancient Greek]] Attic [[Red-figure pottery|red-figure]] [[lekythos]], ca. 470–460 BC, [[National Archaeological Museum, Athens]]]] | |
| [[File:Lady looking into mirror Belur Halebidu.jpg|thumb|A sculpture of a lady looking into a mirror, India]]
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| The first mirrors used by people were most likely pools of dark, still water, or water collected in a primitive vessel of some sort. The earliest manufactured mirrors were pieces of polished stone such as [[obsidian]], a naturally occurring [[volcanic glass]]. Examples of obsidian mirrors found in [[Anatolia]] (modern-day Turkey) have been dated to around 6000 BC.<ref name="Enoch"/> Polished stone mirrors from Central and South America date from around 2000 BC onwards.<ref name="Enoch">[http://www.optvissci.com/pt/re/ovs/pdfhandler.00006324-200610000-00017.pdf History of Mirrors Dating Back 8000 Years], Jay M. Enoch, School of Optometry, University of California at Berkeley</ref> Mirrors of polished copper were crafted in [[Mesopotamia]] from 4000 BC,<ref name="Enoch"/> and in ancient Egypt from around 3000 BC.<ref>[http://www.tekniskamuseet.se/templates/Page.aspx?id=12447 The National Museum of Science and Technology, Stockholm]</ref> In China, bronze mirrors were manufactured from around 2000 BC,<ref>[http://www.chinavoc.com/arts/handicraft/bronze/patternchange.asp Chinavoc.com]</ref> some of the earliest bronze and copper examples being produced by the [[Qijia culture]]. Mirrors made of other metal mixtures ([[alloy]]s) such as copper and tin [[speculum metal]] may have also been produced in China and India.<ref>
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| [http://books.google.com/books?id=BYixSmXUCuMC&pg=PA238&dq=speculum+metal&lr=#v=onepage&q=speculum%20metal&f=false Google Books Search], by Joseph Needham, Gwei-djen Lu, Science and civilisation in China, Volume 5, page 238</ref> Mirrors of speculum metal or any precious metal were hard to produce and were only owned by the wealthy.<ref>[http://books.google.com/books?id=ioNOAAAAMAAJ&pg=PA89&dq=speculum+metal+mirros+of+precious+metal#v=onepage&q=&f=falseGoogle Books Search], Albert Allis, The Scientific American cyclopedia of formulas, page 89</ref>
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| Metal-coated glass mirrors are said to have been invented in [[Sidon]] (modern-day Lebanon) in the first century AD,<ref>[http://www.digitalegypt.ucl.ac.uk/metal/mirrors.html Mirrors in Egypt], Digital Egypt for Universities</ref> and glass mirrors backed with [[gold leaf]] are mentioned by the Roman author [[Pliny the Elder|Pliny]] in his ''[[Natural History (Pliny)|Natural History]]'', written in about 77 AD.<ref>[http://www.umich.edu/~kelseydb/Exhibits/WondrousGlass/RomanGlass-Wondrous.html Wondrous Glass: Images and Allegories], Kelsey Museum of Archaeology</ref> The Romans also developed a technique for creating crude mirrors by coating blown glass with molten lead.<ref>[http://www.c-s-p.org/Flyers/9781847181930-sample.pdf The Book of the Mirror], Cambridge Scholars Publishing, edited by Miranda Anderson</ref>
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| [[Parabolic mirror]]s were described and studied in [[classical antiquity]] by the mathematician [[Diocles (mathematician)|Diocles]] in his work ''On Burning Mirrors''.<ref>pp. 162–164, ''Apollonius of Perga's Conica: text, context, subtext'', Michael N. Fried and Sabetai Unguru, Brill, 2001, ISBN 90-04-11977-9.</ref> [[Ptolemy]] conducted a number of experiments with curved polished iron mirrors,<ref>p. 64, ''Mirror mirror: a history of the human love affair with reflection'', Mark Pendergrast, Basic Books, 2004, ISBN 0-465-05471-4</ref> and discussed plane, convex spherical, and concave spherical mirrors in his ''Optics''.<ref>pp. 38 ff., Ptolemy's Theory of Visual Perception: An English Translation of the "Optics" with Introduction and Commentary, A. Mark Smith, ''Transactions of the American Philosophical Society, new series'' '''86''', No. 2 (1996), pp. iii–300.</ref> [[Parabolic mirror]]s were also described by the physicist [[Ibn Sahl]] in the 10th century,<ref>pp. 465, 468, 469, A Pioneer in Anaclastics: Ibn Sahl on Burning Mirrors and Lenses, Roshdi Rashed, ''Isis'', '''81''', No. 3 (September 1990), pp. 464–491, {{doi|10.1086/355456}}.</ref> and [[Ibn al-Haytham]] discussed [[Curved mirror|concave and convex mirrors]] in both [[Cylinder (geometry)|cylindrical]] and [[Spherical geometry|spherical geometries]],<ref>R. S. Elliott (1966). ''Electromagnetics'', Chapter 1. [[McGraw-Hill]].</ref> carried out a number of experiments with mirrors, and solved the problem of finding the point on a convex mirror at which a ray coming from one point is reflected to another point.<ref name=Deek>Dr. Mahmoud Al Deek. "Ibn Al-Haitham: Master of Optics, Mathematics, Physics and Medicine, ''Al Shindagah'', November–December 2004.</ref> By the 11th century, clear glass mirrors were being produced in [[Al-Andalus|Moorish Spain]].<ref name=Ajram>{{Cite book|author=Dr. Kasem Ajram|title=The Miracle of Islam Science|edition=2nd|publisher=Knowledge House Publishers|year=1992|isbn=0-911119-43-4}}</ref>{{Verify source|date=September 2010}}
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| In China, people began making mirrors with the use of silver-mercury [[amalgam (chemistry)|amalgams]] as early as 500 AD.<ref>Archaeominerology By George Rapp – Springer Verlag Berlin Heidelberg 2009 page 180</ref> Some time during the early [[Renaissance]], European manufacturers perfected a superior method of coating glass with a tin-mercury amalgam.
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| The exact date and location of the discovery is unknown, but in the 16th century, [[Venice]], a city famed for its glass-making expertise, became a centre of mirror production using this new technique. Glass mirrors from this period were extremely expensive luxuries.<ref>[http://links.jstor.org/sici?sici=0039-3630%28199302%2938%3A1%3C3%3ATTMIMT%3E2.0.CO%3B2-8 The Tin-Mercury Mirror: Its Manufacturing Technique and Deterioration Processes], Per Hadsund, Studies in Conservation, Vol. 38, No. 1 (Feb., 1993)</ref> The [[Saint-Gobain]] factory, founded by royal initiative in France, was an important manufacturer, and [[Bohemia]]n and German glass, often rather cheaper, was also important.
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| The invention of the [[silvering|silvered-glass]] mirror is credited to German chemist [[Justus von Liebig]] in 1835.<ref>{{Cite journal| doi = 10.1002/jlac.18560980112 | title = Ueber Versilberung und Vergoldung von Glas | journal = Annalen der Chemie und Pharmacie | volume = 98 | issue = 1 | year = 1856 | pages = 132–139 | first = Justus | last = Liebig}}</ref> His process involved the deposition of a thin layer of metallic silver onto glass through the chemical reduction of [[silver nitrate]]. This silvering process was adapted for mass manufacturing and led to the greater availability of affordable mirrors. Nowadays, mirrors are often produced by the [[wet deposition]] of silver (or sometimes aluminum via vacuum deposition<ref>Glass Association of North America Mirror Website http://www.mirrorlink.org/tech/manufacture.htm</ref>) directly onto the glass substrate.
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| ==Manufacturing==
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| Mirrors are manufactured by applying a [[silvering|reflective coating]] to a suitable [[substrate (materials science)|substrate]]. The most common substrate is glass, due to its transparency, ease of fabrication, rigidity, hardness, and ability to take a smooth finish. The reflective coating is typically applied to the back surface of the glass, so that the reflecting side of the coating is protected from corrosion and accidental damage by the glass on one side and the coating itself and optional paint for further protection on the other.
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| In classical antiquity, mirrors were made of solid metal (bronze, later silver) and were too expensive for widespread use by common people; they were also prone to [[corrosion]]. Due to the low reflectivity of polished metal, these mirrors also gave a darker image than modern ones, making them unsuitable for indoor use with the artificial lighting of the time ([[candle]]s or [[lantern]]s).{{Citation needed|date=September 2009}}
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| The method of making mirrors out of [[flat glass|plate glass]] was invented by 16th-century Venetian glassmakers on the island of [[Murano]], who covered the back of the glass with [[mercury (element)|mercury]], obtaining near-perfect and undistorted reflection. For over one hundred years, Venetian mirrors installed in richly decorated frames served as luxury decorations for palaces throughout Europe, but the secret of the mercury process eventually arrived in London and Paris during the 17th century, due to industrial espionage. French workshops succeeded in large scale industrialization of the process, eventually making mirrors affordable to the masses, although mercury's [[toxicity]] remained a problem{{Citation needed|date=June 2009|reason=was mercury's toxicity recognised then? I think it was considered innocuous until the mid-twentieth century}}.
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| In modern times, the mirror [[Substrate (materials science)|substrate]] is shaped, polished and cleaned, and is then coated. Glass mirrors are most often coated with non-toxic silver<ref>[http://www.mirrorlink.org/tech/manufacture.htm Mirror Manufacturing and Composition]</ref> or aluminium, implemented by a series of coatings:{{Citation needed|date=September 2009}}
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| # [[Tin(II) chloride]]
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| # Silver
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| # Chemical [[catalyst|activator]]
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| # Copper
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| # [[Paint]]
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| The [[tin(II) chloride]] is applied because silver will not bond with the glass. The activator causes the tin/silver to harden. Copper is added for long-term durability.<ref name="How It's Made ep 305">Episode 305 of [[How It's Made]], filmed at [http://www.laverreriewalker.com/ verrerie-walker.com] in [[Anjou, Quebec]], Canada</ref> The [[paint]] protects the coating on the back of the mirror from scratches and other accidental damage.{{Citation needed|date=September 2009}}
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| In some applications, generally those that are cost-sensitive or that require great durability, mirrors are made from a single, bulk material such as polished metal.{{Citation needed|date=September 2009}} For technical applications such as [[laser]] mirrors, the reflective coating is typically applied by [[vacuum deposition]] on the ''front'' surface of the substrate. This eliminates [[refraction]] and double reflections (a weak reflection from the surface of the glass, and a stronger one from the reflecting metal) and reduces absorption of light by the mirror. Technical mirrors may use a silver, aluminium, or gold coating (the latter typically for [[infrared]] mirrors), and achieve reflectivities of 90–95% when new. A protective transparent overcoat may be applied to prevent [[oxidation]] of the reflective layer. Applications requiring higher reflectivity or greater durability, where wide [[bandwidth (signal processing)|bandwidth]] is not essential, use [[dielectric mirror|dielectric coatings]], which can achieve reflectivities as high as 99.999% over a narrow range of wavelengths.{{Citation needed|date=September 2009}}
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| ==Types of glass mirrors==
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| [[File:Johann Jacob Kirstein 001.JPG|thumb|left|18th century [[vermeil]] mirror in the [[Musée des Arts décoratifs, Strasbourg]]]]
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| {{Unreferenced section|date=January 2013}}
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| There are many types of glass mirrors, each representing a different manufacturing process and reflection type.
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| An '''aluminium glass mirror''' is made of a [[float glass]] manufactured using vacuum coating, i.e. aluminium powder is evaporated (or "sputtered") onto the exposed surface of the glass in a vacuum chamber and then coated with two or more layers of waterproof protective paint.
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| A '''low aluminium glass mirror''' is manufactured by coating silver and two layers of protective paint on the back surface of glass. A low aluminium glass mirror is very clear, light transmissive, smooth, and reflects accurate natural colors. This type of glass is widely used for framing presentations and exhibitions in which a precise color representation of the artwork is truly essential or when the background color of the frame is predominantly white.{{Citation needed|date=November 2010}}
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| A '''safety glass mirror''' is made by adhering a special protective film to the back surface of a silver glass mirror, which prevents injuries in case the mirror is broken. This kind of mirror is used for furniture, doors, glass walls, commercial shelves, or public areas.{{Citation needed|date=November 2010}}
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| A '''silkscreen printed glass mirror''' is produced using [[inorganic]] color ink that prints patterns through a special [[silkscreen|screen]] onto glass. Various colors, patterns, and glass shapes are available. Such a glass mirror is durable and more moisture resistant than ordinary printed glass and can serve for over 20 years. This type of glass is widely used for decorative purposes (e.g., on mirrors, table tops, doors, windows, kitchen [[Cutting board|chop board]]s, etc.).{{Citation needed|date=November 2010}}
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| A '''silver glass mirror''' is an ordinary mirror, coated on its back surface with silver, which produces images by reflection. This kind of glass mirror is produced by coating a silver, copper film and two or more layers of waterproof paint on the back surface of float glass, which perfectly resists acid and moisture. A silver glass mirror provides clear and actual images, is quite durable, and is widely used for furniture, bathroom and other decorative purposes.{{Citation needed|date=November 2010}}
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| Decorative glass mirrors are usually handcrafted. A variety of shades, shapes and glass thickness are often available.
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| {{Citation needed|date=November 2010}}
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| ==Effects==
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| {{See also|Mirror image|Specular reflection}}
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| [[File:UniversumUNAM27.JPG|thumb|Photographer taking picture of himself in curved mirror at the [[Universum (UNAM)|Universum museum]] in Mexico City]]
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| ===Shape of a mirror's surface===
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| A beam of light reflects off a mirror at an angle of reflection equal to its [[angle of incidence]] (if the size of a mirror is much larger than the wavelength of light). That is, if the beam of light is shining on a mirror's surface at a <math>\theta</math>° angle vertically, then it reflects from the point of incidence at a <math>\theta</math>° angle from vertically in the opposite direction. This law mathematically follows from the interference of a [[plane wave]] on a flat boundary (of much larger size than the wavelength).
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| * In a '''plane mirror''', a [[parallel (geometry)|parallel]] beam of light changes its direction as a whole, while still remaining parallel; the images formed by a plane mirror are [[virtual image]]s, of the same size as the original object (see [[mirror image]]).
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| * In a '''[[concave mirror]]''', parallel beams of light become a convergent beam, whose rays intersect in the [[Focus (optics)|focus]] of the mirror. Also known as converging mirror
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| * In a '''[[convex mirror]]''', parallel beams become divergent, with the [[ray (optics)|rays]] appearing to diverge from a common point of intersection "behind" the mirror.
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| * '''Spherical concave and convex mirrors''' do not focus parallel rays to a single point due to [[spherical aberration]]. However, the ideal of focusing to a point is a commonly-used approximation. '''[[Parabolic reflector]]s''' resolve this, allowing incoming parallel rays (for example, light from a distant star) to be focused to a small spot; almost an ideal point. Parabolic reflectors are not suitable for imaging nearby objects because the light rays are not parallel.
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| ===Mirror image===
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| {{main|Mirror image}}
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| If one looks in a mirror, one's image reverses (e.g., if one raises one's right hand, one's left hand will appear to go up in the mirror). However, a mirror does not "swap" left and right, any more than it swaps top and bottom. A mirror reverses the forward/backward axis, and we define left and right relative to front and back. Flipping front/back and left/right is equivalent to a rotation of 180 degrees about the vertical axis (in the same way that text which is back-to-front ''and'' upside-down simply looks like it has been rotated 180 degrees on the page). Therefore, looking at an image of oneself with the front/back axis flipped is the same as looking at an image with the left/right axis flipped and the whole figure rotated 180 degrees about the vertical axis, which is exactly what one sees when standing in front of a mirror.
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| ==Applications==
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| [[Image:mirror.globe.arp.500pix.jpg|thumb|right|200px|Reflections in a spherical convex mirror. The photographer is seen at top right.]]
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| [[Image:In Car Micheal Fitzgerald Cork Racing.jpg|thumb|right|200px|A mirror on a [[racing car]].]]
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| ===Safety and easier viewing===
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| ;Convex mirrors
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| :Convex mirrors provide a wider [[field of view]] than flat mirrors, and are often used on vehicles, especially large trucks, to minimize [[Blind spot (automobile)|blind spots]]. They are sometimes placed at [[road junction]]s, and corners of sites such as [[parking lot]]s to allow people to see around corners to avoid crashing into other vehicles or [[shopping cart]]s. They are also sometimes used as part of security systems, so that a single [[video camera]] can show more than one [[angle]] at a time.{{Citation needed|date=November 2010}}
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| ;[[Mouth mirror]]s or "dental mirrors"
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| :Mouth mirrors or "dental mirrors" are used by dentists to allow indirect vision and lighting within the mouth. Their reflective surfaces may be either flat or curved. Mouth mirrors are also commonly used by [[mechanic]]s to allow vision in tight spaces and around corners in equipment.
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| ;[[Rear-view mirror]]s
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| :Rear-view mirrors are widely used in and on vehicles (such as automobiles, or bicycles), to allow drivers to see other vehicles coming up behind them. Some [[motorcycle helmet]]s have a built-in so-called MROS (Multiple Reflective Optic System): a set of reflective surfaces inside the helmet that together function as a rear-view mirror.<ref>http://www.reevu.fr</ref> On rear-view sunglasses, the left end of the left glass and the right end of the right glass work as mirrors.
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| ===One-way mirrors and windows===
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| {{Main|One-way mirror}}
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| ;One-way mirrors
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| :One-way mirrors (also called two-way mirrors) work by overwhelming dim transmitted light with bright reflected light. A true one-way mirror that actually allows light to be transmitted in one direction only without requiring external energy is not possible as it violates the [[second law of thermodynamics]]: if one placed a cold object on the transmitting side and a hot one on the blocked side, radiant energy would be transferred from the cold to the hot object. Thus, though a one-way mirror can be made to appear to work in only one direction at a time, it is actually reflective from either side.
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| ;One-way windows
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| :One-way windows can be made to work with polarized light in the laboratory without violating the second law. This is an apparent paradox that stumped some great physicists, although it does not allow a practical one-way mirror for use in the real world.<ref>{{Cite web|url=http://www.usna.edu/Users/physics/mungan/Scholarship/FaradayIsolators.pdf |title=Faraday Isolators and Kirchhoff's Law: A Puzzle |accessdate=18 July 2006 |last=Mungan |first=C.E. |year=1999 |format=pdf}}</ref><ref>Rayleigh, ''On the magnetic rotation of light and the second law of thermodynamics'', Nature (London), Vol. '''64''', p. 577 (10 October 1901). http://www.nature.com/nature/journal/v64/n1667/abs/064577e0.html</ref> [[Faraday isolator|Optical isolator]]s are one-way devices that are commonly used with lasers.
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| ===Signalling===
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| {{Main|Heliograph}}
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| With the sun as light source, a mirror can be used to signal by variations in the orientation of the mirror. The signal can be used over long distances, possibly up to 60 kilometres on a clear day. This technique was used by [[Indigenous peoples of the Americas|Native American]] tribes and numerous [[military|militaries]] to transmit information between distant outposts.
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| Mirrors can also be used for search to attract the attention of [[search and rescue]] helicopters. Specialized signalling mirrors are available and are often included in military [[survival kit]]s.
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| ===Technology===
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| ====Televisions and projectors====
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| Microscopic mirrors are a core element of many of the largest [[HDTV|high-definition]] televisions and [[video projector]]s. A common technology of this type is [[Texas Instruments]]' [[digital light processing|DLP]]. A DLP chip is a postage stamp-sized microchip whose surface is an array of millions of microscopic mirrors. The picture is created as the individual mirrors move to either reflect light toward the projection surface ([[pixel]] on), or toward a light absorbing surface (pixel off).
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| Other projection technologies involving mirrors include [[LCoS]]. Like a DLP chip, LCoS is a microchip of similar size, but rather than millions of individual mirrors, there is a single mirror that is actively shielded by a [[liquid crystal]] matrix with up to millions of [[pixels]]. The picture, formed as light, is either reflected toward the projection surface (pixel on), or absorbed by the activated [[LCD]] pixels (pixel off). LCoS-based televisions and projectors often use 3 chips, one for each primary color.
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| [[File:Parabolic trough at Harper Lake in California.jpg|thumb||240px|Parabolic trough at Harper Lake in California]]
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| Large mirrors are used in rear projection televisions. Light (for example from a DLP as mentioned above) is "folded" by one or more mirrors so that the television set is compact.<!-- Image with unknown copyright status removed: [[Image:rear_screen_how_it_works_1.jpg]] -->
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| ====Solar power====
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| Mirrors are integral parts of a [[solar power]] plant. The one shown in the picture to the right uses [[concentrated solar power]] from an array of [[parabolic trough]]s.
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| ====Instruments====
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| {{See also|Mirror support cell}}
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| [[File:E-ELT mirror segments under test.jpg|thumb|[[E-ELT]] mirror segments under test.]]
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| [[Telescope]]s and other precision instruments use ''front silvered'' or [[first surface mirrors]], where the reflecting surface is placed on the front (or first) surface of the glass (this eliminates reflection from glass surface ordinary back mirrors have). Some of them use silver, but most are aluminium, which is more reflective at short wavelengths than silver.
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| All of these coatings are easily damaged and require special handling.
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| They reflect 90% to 95% of the incident light when new.
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| The coatings are typically applied by [[vacuum deposition]].
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| A protective overcoat is usually applied before the mirror is removed from the vacuum, because the coating otherwise begins to corrode as soon as it is exposed to oxygen and humidity in the air. ''Front silvered'' mirrors have to be resurfaced occasionally to keep their quality. There are optical mirrors such as [[mangin mirror]]s that are ''second surface mirrors'' (reflective coating on the rear surface) as part of their optical designs, usually to correct [[optical aberration]]s.<ref>[http://www.bobatkins.com/photography/tutorials/mirror.html Mirror Lenses – how good? Tamron 500/8 SP vs Canon 500/4.5L]</ref>
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| [[File:Super-thin Mirror Under Test at ESO.jpg|thumb|left|Deformable thin-shell mirror. It is 1120 millimetres across but just 2 millimetres thick, making it much thinner than most glass windows.<ref>{{cite news|title=Super-thin Mirror Under Test at ESO|url=http://www.eso.org/public/images/potw1307a/|accessdate=19 February 2013|newspaper=ESO Picture of the Week}}</ref>]]
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| The reflectivity of the mirror coating can be measured using a [[Spectrophotometer|reflectometer]] and for a particular metal it will be different for different wavelengths of light. This is exploited in some [[optical]] work to make [[cold mirror]]s and [[hot mirror]]s. A cold mirror is made by using a transparent substrate and choosing a coating material that is more reflective to visible light and more transmissive to [[infrared]] light.
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| A hot mirror is the opposite, the coating preferentially reflects infrared. Mirror surfaces are sometimes given thin film overcoatings both to retard degradation of the surface and to increase their reflectivity in parts of the spectrum where they will be used. For instance, aluminum mirrors are commonly coated with silicon dioxide or magnesium fluoride. The reflectivity as a function of wavelength depends on both the thickness of the coating and on how it is applied.
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| [[Image:Dielectric laser mirror from a dye laser.JPG|thumb|300px|A dielectric coated mirror used in a [[dye laser]]. The mirror is over 99% reflective at 550 [[nanometer]]s, (yellow), but will allow most other colors to pass through.]]
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| [[Image:Laserr mirror from a dye laser for use with rhodamine.JPG|thumb|200px|A dielectric mirror used in [[laser]]s]]
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| For scientific [[optics|optical]] work, [[dielectric mirror]]s are often used. These are glass (or sometimes other material) substrates on which one or more layers of dielectric material are deposited, to form an optical coating. By careful choice of the type and thickness of the dielectric layers, the range of wavelengths and amount of light reflected from the mirror can be specified. The best mirrors of this type can reflect >99.999% of the light (in a narrow range of wavelengths) which is incident on the mirror. Such mirrors are often used in [[laser]]s.
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| In astronomy, [[adaptive optics]] is a technique to measure variable image distortions and adapt a [[deformable mirror]] accordingly on a timescale of milliseconds, to compensate for the distortions.
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| | |
| Although most mirrors are designed to reflect visible light, surfaces reflecting other forms of electromagnetic radiation are also called "mirrors". The mirrors for other ranges of [[electromagnetic waves]] are used in
| |
| optics and [[astronomy]]. Mirrors for radio waves (sometimes known as reflectors) are important elements of [[radio telescope]]s.
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| | |
| =====Face-to-face mirrors=====
| |
| Two or more mirrors placed exactly face to face can give an [[infinite regress]] of reflections. Some devices use this to generate multiple reflections:
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| * [[Fabry–Pérot interferometer]]
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| * [[Laser]] (which contains an [[optical cavity]])
| |
| * 3D [[Kaleidoscope]] to concentrate light<ref>{{cite journal|title= Output irradiance of tapered lightpipes |journal=JOSA A|volume=27|issue=9|page=1985|year=2010|url=http://fisica.uaz.edu.mx/~imoreno/Publicaciones/JOSA2010.pdf|doi=10.1364/JOSAA.27.001985| author=Ivan Moreno|bibcode = 2010JOSAA..27.1985M }}</ref>
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| * momentum-enhanced [[solar sail]]
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| | |
| ====Military applications====
| |
| It has been said that [[Archimedes]] used a large array of mirrors to burn [[Ancient Rome|Roman]] ships during an attack on Syracuse. This has never been proven or disproved; however, it has been put to the test. Recently, on a popular [[Discovery Channel]] show, ''[[MythBusters]]'', a team from [[MIT]] tried to recreate the famous "Archimedes Death Ray". They were [http://web.mit.edu/2.009/www//experiments/deathray/10_Mythbusters.html unsuccessful] at starting a fire on the ship; however, previous attempts to light the boat on fire using only the bronze mirrors available in Archimedes' time were unsuccessful, and the time taken to ignite the craft would have made its use impractical, resulting in the MythBusters team deeming the myth "busted". It was however found that the mirrors made it very difficult for the passengers of the targeted boat to see, likely helping to cause their defeat, which may have been the origin of the myth. (See [[solar power tower]] for a practical use of this technique.)
| |
| | |
| More recently, two skyscrapers designed by architect [[Rafael Viñoly]], the [[Vdara]] in Las Vegas and [[20 Fenchurch Street]] in London, have experienced unusual problems due to their concave curved glass exteriors acting as respectively cylindrical and spherical reflectors for sunlight. In 2010, the Las Vegas Review Journal reported that sunlight reflected off the Vdara's south-facing tower could singe swimmers in the hotel pool, as well as melting plastic cups and shopping bags; employees of the hotel referred to the phenomenon as the "Vdara death ray".<ref>{{Cite web|url = http://www.reviewjournal.com/news/vdara-visitor-death-ray-scorched-hair
| |
| |title = Vdara visitor: 'Death ray' scorched hair}}</ref> In 2013, sunlight reflecting off 20 Fenchurch Street melted parts of a [[Jaguar Cars|Jaguar car]] parked nearby and scorching the carpet of a nearby barber shop.<ref>{{Cite web|url = http://www.npr.org/blogs/thetwo-way/2013/09/03/218536265/death-ray-ii-london-building-reportedly-roasts-cars|title = 'Death Ray II'? London Building Reportedly Roasts Cars}}</ref>
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| ====Seasonal lighting====
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| [[Image:Kibble Palace Mirror.JPG|left|300px|thumb|A multi-facet mirror in the [[Kibble Palace]] conservatory, [[Glasgow]], Scotland]]
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| <!-- If this technique becomes popular, don't let this section grow into a vast list of examples. -->
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| Due to its location in a steep-sided valley, the Italian town of [[Viganella]] gets no direct sunlight for seven weeks each winter. In 2006 a €100,000 computer-controlled mirror, 8×5 m, was installed to reflect sunlight into the town's piazza. In early 2007 the similarly situated village of [[Bondo, Switzerland]], was considering applying this solution as well.<ref>{{Cite news| url=http://news.bbc.co.uk/2/hi/europe/6189371.stm |work=BBC News | title=Italy village gets 'sun mirror' | date=18 December 2006 | accessdate=12 May 2010}}</ref><ref>{{Cite news| url=http://www.cbsnews.com/stories/2007/02/12/ap/world/mainD8N8AED80.shtml | title=Swiss Officials Want to Spread Sunshine, Swiss Officials May Build Giant Mirror to Give Light to Sunless Village – CBS News}} {{Dead link|date=August 2010|bot=RjwilmsiBot}}</ref> In 2013, mirrors were installed to reflect sunlight into the town square in the Norwegian town of [[Rjukan]].<ref>[http://www.bbc.co.uk/news/world-europe-24747720 ''Mirrors finally bring winter sun to Rjukan in Norway''], BBC News, 30 October 2013</ref> Mirrors can be used to produce enhanced lighting effects in greenhouses or conservatories.
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| ===Leisure===
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| ====Art====
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| =====Paintings=====
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| [[File:Titian Venus Mirror (furs).jpg|thumb|right|220px|[[Titian]]'s ''Venus with a mirror'']]
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| Painters depicting someone gazing into a mirror often also show the person's reflection. This is a kind of abstraction—in most cases the angle of view is such that the person's reflection should not be visible. Similarly, in movies and [[Photography|still photography]] an actor or actress is often shown ostensibly looking at him- or herself in the mirror, and yet the reflection faces the camera. In reality, the actor or actress sees only the camera and its operator in this case, not their own reflection.{{Citation needed|date=November 2010}}
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| The mirror is the central device in some of the greatest of European paintings:{{Citation needed|date=November 2010}}
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| *[[Édouard Manet]]'s ''[[A Bar at the Folies-Bergère]]''
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| *[[Titian]]'s ''[[Venus effect|Venus with a Mirror]]''
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| *[[Jan van Eyck]]'s ''[[Arnolfini Portrait]]''
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| *[[Pablo Picasso]]'s ''[[List of Picasso artworks 1931–1940|Girl before a Mirror]]'' (1932)
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| *[[Diego Velázquez]]'s ''[[Las Meninas]]'', wherein the viewer is both the watcher (of a self-portrait in progress) and the watched, and the many adaptations of that painting in various media
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| *[[Paolo Veronese|Veronese]]'s ''Venus with a Mirror''
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| Mirrors have been used by artists to create works and hone their craft:
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| * [[Filippo Brunelleschi]] discovered linear perspective with the help of the mirror.{{Citation needed|date=November 2010}}
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| * [[Leonardo da Vinci]] called the mirror the "master of painters". He recommended, "When you wish to see whether your whole picture accords with what you have portrayed from nature take a mirror and reflect the actual object in it. Compare what is reflected with your painting and carefully consider whether both likenesses of the subject correspond, particularly in regard to the mirror."{{Citation needed|date=November 2010}}
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| * Many [[self-portraits]] are made possible through the use of mirrors:
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| **Without a mirror, the great self-portraits by [[Dürer]], [[Frida Kahlo]], [[Rembrandt]], and [[Van Gogh]] could not have been painted.{{Citation needed|date=November 2010}}
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| **[[M. C. Escher]] used special shapes of mirrors in order to achieve a much more complete view of his surroundings than by direct observation in ''[[Hand with Reflecting Sphere]]'' (also known as ''Self-Portrait in Spherical Mirror'').
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| | |
| Mirrors are sometimes necessary to fully appreciate art work:
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| *[[István Orosz]]'s [[anamorphosis|anamorphic]] works are images distorted such that they only become clearly visible when reflected in a suitably shaped and positioned mirror.{{Citation needed|date=November 2010}}
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| =====Other artistic mediums=====
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| [[File:Trump International Hotel and Tower, Chicago, Illinois, Estados Unidos, 2012-10-20, DD 05.jpg|thumb|[[Trump International Hotel and Tower (Chicago)|Trump International Hotel and Tower]] reflects the skyline along the [[Chicago River]] in downtown Chicago]]
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| Some other contemporary artists use mirrors as the [[List of artistic mediums|material of art]]:
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| * A [[Chinese magic mirror]] is an art in which the face of the bronze mirror projects the same image that was cast on its back. This is due to minute curvatures on its front.<ref name=unesco-courrier>{{cite journal|journal=The Courier|date=October 1988|pages=16–17|url=http://unesdoc.unesco.org/images/0008/000817/081712eo.pdf|title=Magic Mirrors|accessdate=23 August 2011|publisher=Unesco|issn=0041-5278}}</ref>
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| * [[Specular holography]] uses a large number of curved mirrors embedded in a surface to produce three-dimensional imagery.
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| * Paintings on mirror surfaces (such as silkscreen printed glass mirrors)
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| * Sculptures comprised entirely or in part of mirrors
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| **''[[:File:Infinity wulsin.jpg|Infinity Also Hurts]]'' is a mirror, glass and [[silicone]] sculpture by artist, [[Seth Wulsin]]
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| **''[[Sky Mirror]]'' is a [[public art|public sculpture]] by artist, [[Anish Kapoor]]
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| * Special mirror installations
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| **''Follow Me'' mirror labyrinth by artist, [[Jeppe Hein]] (see also, Entertainment: Mirror mazes, below)
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| **''Mirror Neon Cube'' by artist, [[Jeppe Hein]]
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| | |
| ====Decoration====
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| [[File:Overmantel.jpg|thumb|200px|[[Fireplace mantel|Chimneypiece]] and overmantel mirror, c. 1750 V&A Museum no. 738:1 to 3–1897]]
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| Mirrors are frequently used in [[interior decoration]] and as ornaments:
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| * Mirrors, typically large and unframed, are frequently used in [[interior decoration]] to create an illusion of space and amplify the apparent size of a room.{{Citation needed|date=November 2010}} They come also framed in a variety of forms, such as the [[pier glass]] and the overmantle mirror.
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| * Mirrors are used also in some schools of [[feng shui]], an ancient [[Culture of China|Chinese]] practice of placement and arrangement of space, to achieve harmony with the environment.
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| * The softness of old mirrors is sometimes replicated by contemporary artisans for use in interior design. These reproduction antiqued mirrors are works of art and can bring color and texture to an otherwise hard, cold reflective surface. It is an artistic process that has been attempted by many and perfected by few.{{Citation needed|date=November 2010}}
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| * A decorative reflecting [[sphere]] of thin metal-coated glass, working as a reducing wide-angle mirror, is sold as a [[Christmas ornament]] called a ''[[bauble]]''.
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| ====Entertainment====
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| * Illuminated rotating '''[[disco ball]]s''' covered with small mirrors are used to cast moving spots of light around a dance floor.
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| * The '''[[house of mirrors|hall of mirrors]]''', commonly found in [[amusement park]]s, is an attraction in which a number of [[distorting mirror]]s are used to produce unusual reflections of the visitor.
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| * Mirrors are employed in '''[[kaleidoscope]]s''', personal entertainment devices invented in [[Scotland]] by Sir [[David Brewster]].
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| * Mirrors are often used in '''[[Magic (illusion)|magic]]''' to create an [[illusion]]. One effect is called [[Pepper's ghost]].
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| * '''Mirror [[maze]]s''', often found in [[amusement park]]s as well, contain large numbers of mirrors and sheets of glass. The idea is to navigate the disorientating array without bumping into the walls. Mirrors in attractions like this are often made of [[Plexiglas]] as to assure that they do not break.{{Citation needed|date=November 2010}}
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| ====Film and television====
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| * ''[[Candyman (film)|Candyman]]'' is a horror movie about mirrors.
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| * ''[[Mirrors (film)|Mirrors]]'' is a horror movie about mirrors.
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| * ''[[Poltergeist III]]'' features mirrors as a major theme.
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| * ''[[The 10th Kingdom]]'' [[miniseries]] requires the use of a magic mirror for the characters to change setting between modern day New York City (the 10th Kingdom), and the Nine Kingdoms of [[fairy tale]], primarily the 4th Kingdom from [[Snow White]].
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| ====Literature====
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| [[File:Snow White Mirror 4.png|thumb|right|220px|An illustration from page 30 of ''Mjallhvít'' (Snow White) an 1852 Icelandic translation of the [[Brothers Grimm|Grimm]]-version fairytale]]
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| [[File:Taijitu and demon warding mirror.jpg|thumb|right|220px|[[Yin and yang|Taijitu]] within a frame of [[I Ching|trigrams]] and a demon warding mirror. These charms are believed to frighten away evil spirits and to protect the dwelling from bad luck]]
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| | |
| Mirrors play a powerful role in cultural literature.
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| * [[Christian biblical canons|Christian Bible]] passage, 1 Corinthians 13:12 ("[[1 Corinthians 13#"Through a glass, darkly"|Through a Glass Darkly]]"), references a dim mirror image or poor mirror reflection.
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| * '''''[[Narcissus (mythology)|Narcissus]]''''' of [[Greek mythology]] wastes away while gazing, self-admiringly, at his reflection in water.
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| * In the European [[fairy tale]], '''"[[Snow White]]"''' (collected by Brothers Grimm in 1812), the evil queen asks, "[[Magic Mirror (Snow White)|Mirror]], mirror, on the wall... who's the fairest of them all?"
| |
| *In [[Alfred, Lord Tennyson]]'s famous poem '''"[[The Lady of Shalott]]"''' (1833, revised in 1842), the titular character possesses a mirror that enables her to look out on the people of Camelot, as she is under a curse that prevents her from seeing Camelot directly.
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| * [[Lewis Carroll]]'s '''''[[Through the Looking-Glass]] and What Alice Found there''''' (1871) is one of the best-loved uses of mirrors in literature. The text itself utilizes a narrative that mirrors that of its predecessor, [[Alice's Adventures in Wonderland]].{{Citation needed|date=November 2010}}
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| * In [[Oscar Wilde]]'s novel, '''''[[The Picture of Dorian Gray]]''''' (1890), a [[portrait]] serves as a magical mirror that reflects the true visage of the perpetually youthful protagonist, as well as the effect on his soul of each sinful act.<ref>{{cite web|url=http://www.guardian.co.uk/culture/2009/sep/19/oscar-wilde-picture-dorian-gray|title=Mirror, mirror|publisher=The Guardian: Culture Web|work=The Guardian |author=Simon Callow|date=19 September 2009 |accessdate=20 November 2010}}</ref><ref>{{cite web|url=http://www.sparknotes.com/lit/doriangray/|work=Sparknotes.com|title=''The Picture of Dorian Gray''|accessdate=20 November 2010}}</ref>
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| * The short story '''''[[Tlön, Uqbar, Orbis Tertius]]''''' of [[Jorge Luis Borges]] begins with the phrase "I owe the discovery of Uqbar to the conjunction of a mirror and an encyclopedia" and contains other references to mirrors.
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| * The [[Magical objects in Harry Potter|magical objects in the '''''Harry Potter''''' series]] (1997-2011) include the [[Mirror_of_Erised#The_Mirror_of_Erised|Mirror of Erised]] and [[Magical objects in Harry Potter#Two-way_mirrors|two-way mirrors]].
| |
| * Under "Appendix: Variant Planes & Cosmologies" of the '''''[[Dungeons & Dragons]]'' ''[[Manual_of_the_Planes#Dungeons_.26_Dragons_3rd_edition|Manual Of The Planes]]''''' (2000), is The Plane of Mirrors (page 204).<ref>{{cite book| title=Manual Of The Planes| isbn=0-7869-1850-0| year=2001| first=Jeff| last= Grubb| coauthors=David Noonan and Bruce R. Cordell| publisher=Wizards of the Coast| url=http://www.wizards.com/default.asp?x=products/dndacc/882420000}}</ref> It describes the Plane of Mirrors as a space existing behind reflective surfaces, and experienced by visitors as a long corridor. The greatest danger to visitors upon entering the plane is the instant creation of a mirror-self with the opposite alignment of the original visitor.
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| | |
| ==Mirrors and animals==
| |
| [[Image:Whipsnade elephant summer 2006.jpg|thumb|200px|right|The [[Asian elephant]] can recognize its own reflection in a mirror]]
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| [[Image:WW1AcousticMirrorKilnsea(PaulGlazzard)Jan2007.jpg|right|thumb|200px|{{convert|4.5|m|ft|adj=on}} high acoustic mirror near [[Kilnsea]] Grange, East Yorkshire, UK]]
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| | |
| {{Main|Mirror Test}}
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| | |
| Only a few animal species have been shown to have the ability to recognize themselves in a mirror, most of them [[mammal]]s. Experiments have found that the following animals can pass the [[mirror test]]:
| |
| | |
| * All [[great apes]]:
| |
| ** [[Human]]s. Humans tend to fail the mirror test until they are about 18 months old, or what [[psychoanalysis|psychoanalysts]] call the "[[mirror stage]]".<ref>[http://www.ulm.edu/~palmer/ConsciousnessandtheSymbolicUniverse.htm "Consciousness and the Symbolic Universe"]</ref><ref name="coren">{{cite book |title=How dogs think |author=Stanley Coren |isbn=0-7432-2232-6}}</ref><ref name="archer">{{cite book |last=Archer |first=John |year=1992 |title=Ethology and Human Development |publisher=Rowman & Littlefield |isbn=0-389-20996-1}}</ref>
| |
| ** [[Bonobo]]s<ref name="miller">{{cite news |title=Minding the Animals: Ethology and the Obsolescence of Left Humanism |last=Miller |first=Jason |year=2009 |magazine=American Chronicle |url=http://www.americanchronicle.com/articles/view/102661 |accessdate=2009-05-21}}</ref>
| |
| ** [[Chimpanzees]]<ref name="miller"/><ref>{{cite journal |first= Daniel |last=Povinelli |coauthors=de Veer, Monique; Gallup Jr., Gordon; Theall, Laura; van den Bos, Ruud |title=An 8-year longitudinal study of mirror self-recognition in chimpanzees (Pan troglodytes) |journal= Neuropsychologia |volume=41 |issue=2 |pages=229–334 |issn=0028-3932 |doi=10.1016/S0028-3932(02)00153-7|year=2003}}</ref>
| |
| ** [[Orangutan]]s<ref name="natgeo">{{cite web |url= http://www.youtube.com/watch?v=W-pc_M2qI74 |title=National Geographic documentary "Human Ape" |accessdate =2010-06-11}}</ref>
| |
| ** [[Gorilla]]s. Initially, it was thought that gorillas did not pass the test, but there are now several well-documented reports of gorillas (such as [[Koko (gorilla)|Koko]]<ref>Francine Patterson and Wendy Gordon [http://www.animal-rights-library.com/texts-m/patterson01.htm The Case for Personhood of Gorillas]. In ''[[The Great Ape Project]]'', ed. Paola Cavalieri and Peter Singer, St. Martin's Griffin, 1993, pp. 58–77.</ref>) passing the test.
| |
| * [[Bottlenose dolphins]]<ref>{{cite book |title=Self-awareness in Animals and Humans: Developmental Perspectives |author=Marten, K. & Psarakos, S. |chapter=Evidence of self-awareness in the bottlenose dolphin (''Tursiops truncatus'') |editor=Parker, S.T., Mitchell, R. & Boccia, M. |pages=361–379 |year=1995 |publisher=Cambridge University Press |url=http://earthtrust.org/delbook.html |accessdate=2008-10-04}}</ref>
| |
| * [[Orcas]]<ref>{{cite journal |pmid=11334706 |title= Mirror image processing in three marine mammal species: killer whales (Orcinus orca), false killer whales (Pseudorca crassidens) and California sea lions (Zalophus californianus) |year=2001 |last1=Delfour |first1=F |last2=Marten |first2=K |volume=53 |issue=3 |pages=181–190 |journal=Behavioural processes}}</ref>
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| * [[Elephants]]<ref>Joshua M. Plotnik, Frans B.M. de Waal, and Diana Reiss (2006) Self-recognition in an Asian elephant. [[Proceedings of the National Academy of Sciences]] 103(45):17053–17057 10.1073/pnas.0608062103 [http://www.pnas.org/cgi/content/abstract/0608062103v1 abstract]</ref>
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| * [[European Magpie]]s<ref>{{cite journal |first=Helmut |last=Prior |last2=Schwarz |first2=Ariane |last3=Güntürkün |first3=Onur |last4=De Waal |first4=Frans |title=Mirror-Induced Behavior in the Magpie (Pica pica): Evidence of Self-Recognition |journal=PLoS Biology |publisher=Public Library of Science |year=2008 |doi=10.1371/journal.pbio.0060202 |accessdate=2008-08-21 |url= http://biology.plosjournals.org/archive/1545-7885/6/8/pdf/10.1371_journal.pbio.0060202-L.pdf |volume=6 |page=e202 |pmid=18715117 |issue=8 |pmc=2517622 |editor1-last=De Waal |editor1-first=Frans}}</ref>
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| | |
| ==Unusual kinds of mirrors==
| |
| Other types of reflecting device are also called "mirrors".
| |
| | |
| * '''[[Acoustic mirror]]s''' are [[passive device]]s used to reflect and perhaps to focus [[sound wave]]s. Acoustic mirrors were used for selective detection of sound waves, especially during World War II. They were used for detection of enemy aircraft prior to the development of [[radar]]. Acoustic mirrors are used for remote probing of the atmosphere; they can be used to form a narrow [[diffraction-limited system|diffraction-limited]] beam.<ref name="U1">{{Cite journal
| |
| | url=http://www.springerlink.com/content/w613354427150024
| |
| | author=M. A. Kallistratova
| |
| | title=Physical grounds for acoustic remote sensing of the atmospheric boundary layer
| |
| | journal=Lecture Notes in Earth Sciences
| |
| | volume=69
| |
| | pages=3–34
| |
| | year=1997
| |
| | doi=10.1007/BFb0009558
| |
| | series=Lecture Notes in Earth Sciences
| |
| | isbn=3-540-61612-8
| |
| }}</ref> They can also be used for underwater imaging.
| |
| * '''Active mirrors''' are mirrors that [[amplifier|amplify]] the light they reflect. They are used to make [[disk laser]]s.<ref name="Ueda">{{Cite journal| url=http://bookstore.spie.org/index.cfm?fuseaction=DetailPaper&ProductId=143686&coden=PSISDG
| |
| | author=K. Ueda| coauthors=N. Uehara| title=Laser-diode-pumped solid state lasers for gravitational wave antenna| journal=[[Proceedings of SPIE]]| volume=1837| pages=336–345| year=1993| doi=10.1117/12.143686}} {{Dead link|date=May 2010}}</ref> The amplification is typically over a narrow range of [[wavelength]]s, and requires an external source of power.
| |
| * '''[[Atomic mirror]]s''' are devices which reflect [[matter waves]]. Usually, atomic mirrors work at [[grazing incidence]]. Such mirrors can be used for atomic [[interferometry]] and atomic [[holography]]. It has been proposed that they can be used for non-destructive imaging systems with [[nanometer]] resolution.<ref name="nanoscope">{{Cite journal
| |
| | url=http://stacks.iop.org/0953-4075/39/1605
| |
| | author= D. Kouznetsov
| |
| | coauthors=H. Oberst, K. Shimizu, A. Neumann, Y. Kuznetsova, J.-F. Bisson, K. Ueda, S. R. J. Brueck
| |
| | title=Ridged atomic mirrors and atomic nanoscope
| |
| | journal=[[Journal of Physics B]]
| |
| | volume=39
| |
| | pages=1605–1623
| |
| | year=2006
| |
| | doi=10.1088/0953-4075/39/7/005
| |
| |bibcode = 2006JPhB...39.1605K
| |
| | issue=7 }}</ref>
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| * '''[[Cold mirror]]s''' are [[dielectric]] mirrors that reflect the entire [[visible light spectrum]], while efficiently transmitting [[infrared]] wavelengths. These are the converse of hot mirrors.
| |
| * '''[[Corner reflector]]s''' use three flat mirrors to reflect light back towards its source, they may also be implemented with prisms that reflect using total internal reflection that have no mirror surfaces. They are used for emergency location, and even [[laser ranging]] to the [[Moon]].
| |
| * '''[[Hot mirror]]s''' reflect infrared light while allowing visible light to pass. These can be used to separate useful light from unneeded infrared to reduce heating of components in an optical device. They can also be used as dichroic [[beamsplitters]]. (Hot mirrors are the converse of cold mirrors.)
| |
| * '''Metallic reflectors''' are used to reflect infrared light (such as in [[space heater]]s or [[microwave]]s).
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| * '''[[Non-reversing mirror]]s''' are mirrors that provide a non-reversed image of their subjects.
| |
| * '''X-ray mirrors''' produce specular reflection of [[X-ray]]s. All known types work only at angles near grazing incidence, and only a small fraction of the rays are reflected.<ref name="pro00">{{Cite journal
| |
| | title= X-ray parabolic collimator with depth-graded multilayer mirror
| |
| | author= V.V.Protopopov
| |
| | coauthors= V.A.Shishkov, and V.A.Kalnov
| |
| | pages=4380–4386
| |
| | journal=[[Review of Scientific Instruments]]
| |
| | year= 2000
| |
| | volume=71
| |
| | issue=12
| |
| | doi= 10.1063/1.1327305
| |
| |bibcode = 2000RScI...71.4380P }}</ref> See also [[X-ray optics]].
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| ==See also==
| |
| {{cmn|4|
| |
| * [[Anamorphosis]]
| |
| * [[Aranmula kannadi]]
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| * [[Bronze mirror]]
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| * [[Chirality (mathematics)]]
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| * [[Cold mirror]] and [[Hot mirror]]
| |
| * [[Curved mirror]]
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| * [[Deformable mirror]]
| |
| * [[Dielectric mirror]]
| |
| * [[Digital micromirror device]]
| |
| * [[Distorting mirror]]
| |
| * [[Home decor]]
| |
| * [[Honeycomb mirror]]
| |
| * [[Infinity mirror]]
| |
| * [[List of telescope parts and construction]]
| |
| * [[Mirror armour]] (an oriental partial plate armour from polished metal mirrors)
| |
| * ''[[Mirror Mirror: a history of the human love affair with reflection]]'' (book)
| |
| * [[Mirror writing]]
| |
| * [[Mirrors in Mesoamerican culture]]
| |
| * [[Perfect mirror]]
| |
| * [[Periscope]]
| |
| * [[Rear-view mirror]]
| |
| * [[Reflectivity]]
| |
| * [[Silvering]]
| |
| * [[Spectrophobia]]
| |
| * [[TLV mirror]] — An ancient type of Chinese mirror from the [[Han Dynasty]].
| |
| * [[Two-way mirror]] (Also known as [[Two-way mirror|one-way mirror]])
| |
| * [[Venus effect]]
| |
| }}
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| | |
| ==References==
| |
| {{Reflist|30em}}
| |
| | |
| ==Bibliography==
| |
| * ''Mirror, Mirror: A History of the Human Love Affair with Reflection'', Mark Pendergrast. Basic Books (2003). ISBN 0-465-05471-4 .
| |
| * ''On reflection'', [[Jonathan Miller]], National Gallery Publications Limited (1998). ISBN 0-300-07713-0 .
| |
| * ''The Mirror: A History'', Sabine Melchior-Bonnet, Routledge, 2001, ISBN 0-415-92448-0
| |
| | |
| ==External links==
| |
| {{Wiktionary|mirror}}
| |
| {{wikiquote}}
| |
| {{Commons category|Mirrors}}
| |
| * [http://www.mirrorlink.org/tech/manufacture.htm ''Mirror Manufacturing and Composition'', Mirrorlink]
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| * [http://www.americanchemistry.com/s_chlorine/science_sec.asp?CID=1242&DID=4720&CTYPEID=113 ''Stannous Chloride: Silvering Mirrors'', American Chemical Association]
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| * [http://www.youtube.com/watch?v=8Y-kWGe01jE Video of Mirror Making]
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| * [http://books.google.com/books?hl=en&id=P-c1g6QIPHIC&dq=mirror+history&printsec=frontcover&source=web&ots=LfmtU-zNjJ&sig=ZqkBUsx18w_zoq_lH5-7Pl1zTIk#PPP1,M1 The Mirror: A History by Sabine Melchior-Bonnet at Google Books]
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| * [http://www.glasswebsite.com/video/mirror.asp How Mirrors Are Made (video)], Glass Association of North America (GANA)
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| <!--*[http://knol.google.com/k/not-just-mirrors/when-a-mirror-is-not-just-for-looking-in/3d6s19yzcqi5p/2?locale=en&path_author=not-just-mirrors&path_title=when-a-mirror-is-not-just-for-looking-in#view Knol/Google Mirror page]-->
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| {{Use dmy dates|date=May 2012}}
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| [[Category:Reflective building components]]
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| [[Category:Mirrors| ]]
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| [[Category:Glass applications]]
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