A mirror is an object with a surface that has good specular reflection; that is, it is smooth enough to form an image. Specular reflection is the perfect Mirror -like reflection of light (or sometimes other kinds of Wave) from a surface in which light from a single incoming An image (from Latin imago) or picture is an artifact usually two-dimensional that has a similar appearance to some subject &mdashusually The most familiar type of mirror is the plane mirror, which has a flat surface. A plane mirror is a Mirror with a planar reflective surface For Light rays striking a plane mirror the angle of reflection equals Curved mirrors are also used, to produce magnified or demagnified images or focus light or simply distort the reflected image. A curved mirror is a Mirror with a curved reflective surface which may be either convex (bulging outward or concave (bulging inward Magnification is the process of enlarging something only in appearance not in physical size

Mirrors are most commonly used for personal grooming (in which case the old-fashioned term "looking-glass" can be used), decoration, and architecture. Personal grooming (also called titivating) is the art of cleaning grooming and maintaining parts of the body Mirrors are also used in scientific apparatus such as telescopes and lasers, cameras, and industrial machinery. A telescope is an instrument designed for the observation of remote objects and the collection of Electromagnetic radiation. A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. A camera is a device used to capture images either as still Photographs or as sequences of moving images ( Movies or Videos. Most mirrors are designed for visible light; however, mirrors designed for other types of waves or other wavelengths of electromagnetic radiation are also used, especially in optical instruments. In Physics wavelength is the distance between repeating units of a propagating Wave of a given Frequency. Electromagnetic radiation takes the form of self-propagating Waves in a Vacuum or in Matter.

Contents 1 History 2 Manufacturing 3 Effects 4 Applications 4.1 Safety and easier viewing 4.2 Two-way mirrors 4.3 Signalling 4.4 Technology 4.4.1 Televisions and projectors 4.4.2 Instruments 4.4.2.1 Face-to-face mirrors 4.4.3 Military applications 4.4.4 Seasonal lighting 4.5 Leisure 4.5.1 Decoration 4.5.2 Entertainment 4.5.3 Art 5 Mirrors and superstition 6 Mirrors and animals 7 Unusual types of mirror 8 See also 9 Notes 10 Bibliography 11 External links

History

The earliest manufactured mirrors were pieces of polished stone such as obsidian, a naturally occurring volcanic glass. Obsidian is a naturally occurring Glass formed as an extrusive Igneous rock. Examples of obsidian mirrors found in Anatolia (modern-day Turkey) have been dated to around 6000 BC. Anatolia (Anadolu Ανατολία Anatolía) or Asia minor, comprising most of modern Turkey, is the geographic region bounded by the Black Polished stone mirrors from central and south America date from around 2000 BC onwards. ^[1]

Mirrors of polished copper were crafted in Mesopotamia from 4000 BC,^[1] and in ancient Egypt from around 3000 BC. Mesopotamia (from the Greek meaning "land between the rivers" is an area geographically located between the Tigris and Euphrates rivers largely corresponding ^[2] In China, bronze mirrors were manufactured from around 2000 BC. ^[3]

Metal-coated glass mirrors are said to have been invented in Sidon (modern-day Lebanon) in the first century AD,^[4] and glass mirrors backed with gold leaf are mentioned by the Roman author Pliny in his Natural History, written in about 77 AD. Sidon,or Saïda, ( Arabic ar صيدا; Phoenician phoenician yodh Metal leaf is a thin foil used for decoration It is also called composition leaf or schlagmetal. Gaius or Caius Plinius Secundus, ( AD 23 – August 25, AD 79 better known as Pliny the Elder, was an ancient Author Naturalis Historia ( Latin for "Natural History" is an Encyclopedia written Circa AD 77 by Pliny the Elder. ^[5] The Romans also developed a technique for creating crude mirrors by coating blown glass with molten lead. ^[6]

Some time during the early Renaissance, European manufacturers perfected a superior method of coating glass with a tin-mercury amalgam. The Renaissance (from French Renaissance, meaning "rebirth" Italian: Rinascimento, from re- "again" and nascere 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. Venice ( Italian: Venezia, Venetian: Venesia or Venexia) is a city in Northern Italy, the capital of the Glass mirrors from this period were extremely expensive luxuries. ^[7] The Saint-Gobain factory, founded by royal initiative in France, was an important manufacturer, and Bohemian and German glass, often rather cheaper, was also important. Saint-Gobain SA ( is a French Multinational corporation, founded in 1665 in Paris and headquartered on the outskirts of Paris at La Bohemia (Čechy; Bohemia Czechy is a historical region in central Europe, occupying the western two-thirds of the traditional Czech Lands, currently the

The invention of the silvered-glass mirror is credited to German chemist Justus von Liebig in 1835. Silvering is the chemical process of coating Glass with a reflective substance Justus von Liebig ( May 12, 1803 &ndash April 18, 1873) was a German Chemist 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 vacuum deposition of aluminium (or sometimes silver) directly onto the glass substrate. Vacuum deposition or vacuum coating is a family of processes used to deposit layers atom-by-atom or molecule-by-molecule at sub- Atmospheric pressure ( Vacuum WikipediaNaming

Manufacturing

Most mirrors are made by applying a reflective coating to a suitable substrate. The most common such substrate is glass, due to its ease of fabrication, its rigidity, and its ability to take a smooth finish. Glass in the common sense refers to a Hard, Brittle, transparent Solid, such as that used for Windows many The reflective coating is typically applied to the back surface of the glass, so that it is protected from corrosion and accidental damage. (Glass is much more scratch-resistant than most substrates. )

The substrate is shaped, polished and cleaned, and is then coated. Glass mirrors are most often coated with silver or aluminium, implemented by a series of coatings:

1. tin
2. silver
3. chemical activator
4. copper
5. paint

The tin is applied because the silver will not bond with the glass. Silver (ˈsɪlvɚ is a Chemical element with the symbol " Ag " (argentum from the Ancient Greek: ἀργήντος - argēntos gen WikipediaNaming The activator causes the tin/silver to harden. Copper is added for long-term durability. ^[8] The paint protects the coating on the back of the mirror from scratches and other accidental damage.

In some applications, generally those that are cost-sensitive or that require great durability, mirrors are instead made from a single, bulk material such as polished metal.

For technical applications such as laser mirrors, the reflective coating is typically applied by vacuum deposition on the front surface of the substrate. A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. Vacuum deposition or vacuum coating is a family of processes used to deposit layers atom-by-atom or molecule-by-molecule at sub- Atmospheric pressure ( Vacuum This eliminates double reflections and reduces absorption of light in the mirror. Cheaper technical mirrors use a silver, aluminium, or gold coating (the latter typically for infrared mirrors), and achieve reflectivities of 90–95% when new. Gold (ˈɡoʊld is a Chemical element with the symbol Au (from its Latin name aurum) and Atomic number 79 Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of A protective overcoat may be applied to prevent oxidation of the reflective layer. Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state Applications requiring higher reflectivity or greater durability use dielectric coatings, which can achieve reflectivities as high as 99. A dielectric mirror is a type of a Mirror composed of multiple thin layers of Dielectric material typically deposited on a substrate of Glass 999% over a narrow range of wavelengths.

Effects

See also Mirror image and Specular reflection

In a plane mirror, a parallel beam of light changes its direction as a whole, while still remaining parallel; the images formed by a plane mirror are virtual images, of the same size as the original object (see mirror image). Light, or visible light, is Electromagnetic radiation of a Wavelength that is visible to the Human eye (about 400–700 In Optics, a virtual image is an image in which the outgoing rays from a point on the object never actually intersect at a point "Mirror Image" is an episode of the Television series The Twilight Zone. There are also concave mirrors, where a parallel beam of light becomes a convergent beam, whose rays intersect in the focus of the mirror. A curved mirror is a Mirror with a curved reflective surface which may be either convex (bulging outward or concave (bulging inward In the absence of a more specific context convergence denotes the approach toward a definite value as time goes on or to a definite point a common view or opinion or In Geometrical optics, a focus, also called an image point, is the point where Light rays originating from a point on the object converge. Lastly, there are convex mirrors, where a parallel beam becomes divergent, with the rays appearing to diverge from a common intersection "behind" the mirror. A curved mirror is a Mirror with a curved reflective surface which may be either convex (bulging outward or concave (bulging inward In Optics, a ray is an idealized narrow Beam of light. Rays are used to model the propagation of Light through an optical system by dividing the real light Spherical concave and convex mirrors do not focus parallel rays to a single point due to spherical aberration. spherical-aberration-diskjpg|thumb|300 px|left|A Point source as imaged by a system with negative (top zero (center and positive (bottom spherical aberration However, the ideal of focusing to a point is a commonly-used approximation. Parabolic reflectors resolve this, allowing incoming parallel rays (for example, light from a distant star) to be focused to a small spot; almost an ideal point. A parabolic reflector (or dish or mirror) is a Parabola -shaped reflective device used to collect or distribute Energy such as Parabolic reflectors are not suitable for imaging nearby objects because the light rays are not parallel.

A beam of light reflects off a mirror at an angle of reflection that is 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 30° angle from vertical, then it reflects from the point of incidence at a 30° angle from vertical 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). In the Physics of Wave propagation (especially Electromagnetic waves, a plane wave (also spelled planewave) is a constant-frequency wave whose

Applications

Safety and easier viewing

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. Vehicles, derived from the Latin word vehiculum, are non-living Means of transport. The bicycle, cycle, or bike is a pedal-driven, human-powered vehicle with two wheels attached to a frame, one behind Some motorcycle helmets 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. A motorcycle helmet is a type of protective headgear used by Motorcycle riders [1] There exist rear view sunglasses, of which the left end of the left glass and the right end of the right glass work as mirrors. Sunglasses or sun glasses are a visual aid variously termed Spectacles or Glasses, which feature lenses that are coloured or darkened to prevent strong

Convex mirrors are used to provide a wider field of view than a flat mirror. The field of view (also field of vision) is the angular extent of the observable world that is seen at any given moment They are sometimes placed at road junctions, and corners of places such as parking lots to allow people to see around corners to avoid crashing into other vehicles or shopping carts. A road junction is a location where vehicular Traffic going in different directions can proceed in a controlled manner designed to minimize accidents Parking lot (called a car park in Australia and the UK) is a cleared area that is more or less level and is intended for Parking vehicles A shopping cart (also called a trolley in British, Australian English, and New Zealand English; sometimes referred to as a carriage 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. A video camera is a Camera used for electronic Motion picture acquisition initially developed by the Television industry but now common in other applications In Geometry and Trigonometry, an angle (in full plane angle) is the figure formed by two rays sharing a common Endpoint, called

Mouth mirrors or "dental mirrors" are used by dentists to allow indirect vision and lighting within the mouth. A mouth mirror or dentist's mirror is an instrument in Dentistry commonly used in the dental armamentarium Dentistry' is the "evaluation diagnosis prevention and/or treatment (nonsurgical surgical or related procedures of diseases disorders and/or conditions of the oral cavity Their reflective surfaces may be either flat or curved. Mouth mirrors are also commonly used by engineers to allow vision in tight spaces and around corners in equipment. An engineer is a person professionally engaged in a field of Engineering.

Two-way mirrors

Main article: Two-way mirror

A two-way mirror, also sometimes referred to as a one-way mirror or one-way glass, reflects some percentage of the light and lets some other percentage pass. A two-way mirror, also called a one-way mirror, is a Mirror which is partially reflective and partially transparent It is a sheet of glass coated with a layer of metal only a few dozen atoms thick, allowing some of the light through the surface (from both sides). It is used between a dark room and a brightly lit room. People on the brightly lit side see their own reflection — it looks like a normal mirror. People on the dark side see through it — it looks like a transparent window. In Optics, transparency (also called pellucidity) is the Material property of allowing It may be used to observe criminal suspects or customers. The same type of mirror, when used in an optical instrument, is called a half-silvered mirror or beam splitter. An optical instrument either processes Light waves to enhance an image for viewing or analyzes light waves (or Photons to determine one of a number of characteristic A beam splitter is an optical device that splits a beam of Light in two Its purpose is to split a beam of light so that half passes straight through, while the other half is reflected — this is useful for interferometry. Interferometry is the technique of using the pattern of Interference created by the superposition of two or more Waves to diagnose the properties of The reality television program Big Brother makes extensive use of two-way mirrors throughout its set to allow cameramen in special black hallways to use movable cameras to videotape contestants without their coming in contact with the workers. Big Brother is a Reality television show where in each series a group of people live together in the Big Brother House isolated from the outside world but continuously

Contrary to popular belief, passive one-way mirrors that operate directionally between equally lit rooms do not exist. The laws of physics do not allow for real, passive one-way mirrors or windows (ones that do not need external energy); if such a device were possible, one could break the second law of thermodynamics and make energy flow from a cold object to a hot one, by placing such a mirror between them. The second law of Thermodynamics is an expression of the universal law of increasing Entropy, stating that the entropy of an Isolated system which One-way windows can be made to work with polarized light, however, without violating the second law. ^[9][10] Optical isolators are one-way devices that are commonly used with lasers. An optical isolator, or optical diode, is an optical component which allows the transmission of light in only one direction

Signalling

With the sun as light source, a mirror can be used to signal by variations in the orientation of the mirror. The Sun (Sol is the Star at the center of the Solar System. The signal can be used over long distances, possibly up to 60 kilometres on a clear day. The kilometre ( American spelling: kilometer) symbol km is a unit of Length in the Metric system, equal to one thousand This technique was used by Native American tribes and numerous militaries to transmit information between distant outposts. For indigenous peoples in the United States other than Hawaii and Alaska see also Native Americans in the United States. A military is an Organization authorized by its Nation to use force usually including use of Weapons in defending its Country (or by attacking

Mirrors can also be used for rescue, especially to attract the attention of search and rescue helicopters. Specialised signalling mirrors are available and are often included in military survival kits.

Technology

Televisions and projectors

Microscopic mirrors are a core element of many of the largest high-definition televisions and video projectors. High-definition television (HDTV is a Digital television Broadcasting system with higher resolution than traditional television systems (standard-definition Television ( TV) is a widely used Telecommunication medium for sending ( Broadcasting) and receiving moving Images, either monochromatic A common technology of this type is Texas Instruments' DLP. Texas Instruments ( better known in the electronics industry (and popularly as TI, is an American company based in Dallas, Texas, USA Digital Light Processing (DLP is a Trademark owned by Texas Instruments, representing a technology used in projectors and Video projectors It was A DLP chip is a postage stamp-sized microchip whose surface is comprised of 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). In Digital imaging, a pixel ( pict ure el ement is the smallest piece of information in an image

Other projection technologies involving mirrors include LCoS. Liquid crystal on silicon ( LCOS or LCoS) is a "micro-projection" or "micro-display" Technology typically applied in projection 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. Liquid crystals are substances that exhibit a phase of matter that has properties between those of a conventional Liquid, and those of a Solid In Digital imaging, a pixel ( pict ure el ement is the smallest piece of information in an image The picture is 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.

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.

Instruments

Telescopes 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). A telescope is an instrument designed for the observation of remote objects and the collection of Electromagnetic radiation. Some of them use silver, but most are aluminum, which is more reflective at short wavelengths than silver. All of these coatings are easily damaged and require special handling. They reflect 90% to 95% of the incident light when new. The coatings are typically applied by vacuum deposition. Vacuum deposition or vacuum coating is a family of processes used to deposit layers atom-by-atom or molecule-by-molecule at sub- Atmospheric pressure ( Vacuum 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.

The reflectivity of the mirror coating can be measured using a 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 mirrors and hot mirrors. A cold mirror is a specialized Dielectric mirror, a Dichroic filter, that reflects the entire Visible light spectrum while very efficiently transmitting A hot mirror is a specialized Dielectric mirror, a Dichroic filter, often employed to protect optical systems by reflecting Infrared light back into a light 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. Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of 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.

For scientific optical work, dielectric mirrors are often used. A dielectric mirror is a type of a Mirror composed of multiple thin layers of Dielectric material typically deposited on a substrate of Glass 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 lasers. A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission.

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. Adaptive optics (AO is a Technology used to improve the performance of optical systems by reducing the effects of rapidly changing optical distortion Deformable mirror (DM represent the most convenient tool for Wavefront control and correction of optical Aberrations Deformable mirrors are used in combination with

Although the most of 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. Electromagnetic radiation takes the form of self-propagating Waves in a Vacuum or in Matter. Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study Mirrors for radio waves are important elements of radio telescopes. A radio telescope is a form of directional Radio antenna used in Radio astronomy and in tracking and collecting data from Satellites

A Mangin mirror is a combination lens and concave mirror and is widely used in optical instruments and even sometimes in cameras. In Optics, a Mangin mirror is a combined lens-mirror ( Catadioptric) system consisting of a concave lens with a reflective rear side [2] [3][4]

Face-to-face mirrors

Some devices use two or more mirrors facing one another to generate multiple reflections:

• Fabry-Pérot interferometer
• Laser (which contains an optical cavity)
• some types of catoptric cistula
• momentum-enhanced solar sail[5]

The reflected images between these mirrors give the appearance of an infinite regress. A laser is a device that emits Light ( Electromagnetic radiation) through a process called Stimulated emission. An optical cavity or optical resonator is an arrangement of Mirrors that forms a Standing wave Cavity resonator for Light waves Optical A catoptric cistula, also called a catoptric theatre or chest, is a box with several sides lined with Mirrors so as to magnify or multiply images of Solar sails (also called light sails or photon sails, especially when they use Light sources other than the Sun) are a proposed form of An infinite regress in a series of propositions arises if the truth of proposition P 1 requires the support of proposition P 2 and for any proposition

Military applications

It has been said that Archimedes used a large array of mirrors to burn Roman ships during an attack on Syracuse. Archimedes of Syracuse ( Greek:) ( c. 287 BC – c 212 BC was a Greek mathematician, Physicist, Engineer Ancient Rome was a Civilization that grew out of a small agricultural community founded on the Italian Peninsula as early as the 10th century BC This has never been proven or disproved; however, many have put it to the test. Recently, on a popular Discovery Channel show, MythBusters, a team from MIT tried to recreate the famous "Archimedes Death Ray". Discovery Channel is an American Satellite and Cable TV channel (also delivered via IPTV, Terrestrial television and MythBusters is a Popular science Television program produced by Australian firm Beyond Television Productions originally for the They were successful at starting a fire on a ship at 75 feet away; 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". (However, see solar power tower for a practical use of this technique. The solar power tower (also known as 'Central Tower' power plants or ' Heliostat ' power plants or power towers is a type of Solar furnace using a tower to receive )

Seasonal lighting

Due to its location in a steep-sided valley, the Italian town of Viganella gets no direct sunlight for seven weeks each winter. Viganella is a Comune (municipality in the Province of Verbano-Cusio-Ossola in the Italian region Piedmont, located about 120 km 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. Bondo is a municipality in the district of Maloja in the Swiss canton of Graubünden. ^[11][12]

Leisure

Decoration

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. Interior decoration or decor is the Art of decorating a room so that it is attractive easy to use and functions well with the existing Architecture

Mirrors are used also in some schools of feng shui, an ancient Chinese practice of placement and arrangement of space to achieve harmony with the environment. Feng shui ( ˈfəŋˌʃueɪ fehng-shway in English is an ancient Chinese system of Aesthetics believed to utilize the Laws of both heaven (astronomy and earth (geography The Culture of China (traditional Chinese 中國文化 simplified Chinese 中国文化 is home to one of the world's oldest and most complex Civilizations covering a history

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.

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. "Globose" redirects here See also Globose nucleus. A sphere (from Greek σφαίρα - sphaira, "globe Christmas ornaments are Decorations (usually made of Glass, Metal, Wood or Ceramics that are used to festoon a Christmas

Entertainment

The hall of mirrors, commonly found in amusement parks, is an attraction in which a number of distorted mirrors are used to produce unusual reflections of the visitor. A house of mirrors or hall of mirrors is a traditional attraction at Funfairs (carnivals and Amusement parks The basic concept behind a house of mirrors Theme park is the generic term for a collection of rides and other Entertainment attractions assembled for the purpose of entertaining a large group Mirror mazes, also found in amusement parks, contain large numbers of mirrors and sheets of glass. The idea is to navigate the disorientating array without bumping into the walls.

Mirrors are often used in magic to create an illusion. An illusion is a distortion of the senses revealing how the Brain normally organizes and interprets sensory stimulation One effect is called Pepper's ghost. For the Philadelphia, Pennsylvania -based rock ensemble see Pepper's Ghost (band. Illuminated rotating disco balls covered with small mirrors are used to cast moving spots of light around a dance floor. A disco ball, mirror ball, glitter ball, or ball mirror is a roughly spherical object that reflects light directed at it in many directions Mirrors are employed in kaleidoscopes, personal entertainment devices invented in Scotland by sir David Brewster. A kaleidoscope is a tube of Mirrors containing loose colored Beads Pebbles or other small colored objects Scotland ( Gaelic: Alba) is a Country in northwest Europethat occupies the northern third of the island of Great Britain. Sir David Brewster, FRS ( 11 December 1781 &ndash 10 February 1868) was a Scottish scientist inventor and writer

Art

Filippo Brunelleschi discovered linear perspective with the help of the mirror, Leonardo da Vinci called the mirror the "master of painters". Filippo Brunelleschi (1377 – April 15, 1446) was one of the foremost architects and engineers of the Italian Renaissance. Leonardo di ser Piero da Vinci ( April 15 1452 – May 2 1519 was an Italian Polymath, having been a scientist Mathematician, Engineer 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. The mirror is the central device in some of the greatest of European paintings: Jan Van Eyck's Arnolfini Portrait, Diego Velazquez's Las Meninas and Edouard Manet’s A Bar at the Folies-Bergère. Jan van Eyck or Johannes de Eyck (jɑn vɑn ɛik (before c 1395 &ndash before July 9, 1441) was an Early Netherlandish painter active The Arnolfini Portrait is a Painting in oils on Oak Panel executed by the Early Netherlandish painter Jan van Diego Rodríguez de Silva y Velázquez ( June 6, 1599 &ndash August 6, 1660) was a Spanish painter who was the leading Las Meninas ( Spanish for The Maids of Honour) is a 1656 painting by Diego Velázquez (1599–1660 the leading artist of the A Bar at the Folies-Bergère, painted and exhibited at the Paris Salon in 1882, was the last major work by French painter Édouard Manet Without a mirror, the great self portraits by Dürer, Rembrandt, Van Gogh and Frida Kahlo could not have been painted. A Self-portrait is a representation of an artist drawn painted photographed or sculpted by the artist Albrecht Dürer (ˈalbʀɛçt ˈdyʀɐ ( May 21, 1471 &ndash April 6, 1528) was a German painter, Printmaker Rembrandt Harmenszoon van Rijn (July 15 1606 &ndash October 4 1669 was a Dutch painter and etcher. Frida Kahlo (July 6 1907 – July 13 1954 was a Mexican painter, who has achieved great international popularity M. C. Escher used special shapes of mirrors in order to have a much more complete view of the surroundings than by direct observation (Hand with Reflecting Sphere). Maurits Cornelis Escher (17 June 1898 – 27 March 1972 usually referred to as M Hand with Reflecting Sphere also known as Self-Portrait in Spherical Mirror is a lithograph print by Dutch artist M István Orosz’s anamorphic works are images distorted such way that they only become clearly visible when reflected in a suitably-shaped and positioned mirror. István Orosz (b October 24 1951 Kecskemét) Hungarian painter, printmaker Graphic designer and animated film director is known for Anamorphic format is a term that can be used either for the Cinematography technique of capturing a Widescreen picture on standard 35 mm film, or other Some other contemporary artists use mirrors as the material of art, like in mirror-sculptures and paintings on mirror surfaces. Some artists build special mirror installations as the neon mirror cubes by Jeppe Hein. Jeppe Hein (born 1974 Copenhagen, Denmark) is an artist based in Berlin.

Painters depicting someone in front of 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 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.

Mirrors and superstition

It is a common superstition that someone who breaks a mirror will receive seven years of bad luck. Superstition ( Latin superstitio, literally "standing over" derived perhaps from standing in awe used in Latin as a unreasonable or excessive belief One of the many reasons for this belief is that the mirror is believed to reflect part of the soul, therefore, breaking the mirror will break part of the soul. The soul, according to many religious and philosophical beliefs is the self-awareness, or Consciousness, unique to a particular living However, the soul is said to regenerate every seven years, thus coming back unbroken. To counter this one of many rituals has to be performed, the easiest of which is to stop the mirror from reflecting the broken soul by grinding it to dust. The belief might also simply originate from the high cost of mirrors in times gone past.

According to legend, a vampire has no reflection in mirrors because it is an undead creature and has already lost its soul. Vampires are mythological or folkloric revenants who subsist by feeding on the blood of the living Undead is a collective name for fictional beings that are deceased yet behave as if alive

Another superstition claims it is bad luck to have two mirrors facing each other.

Mirrors and animals

Experiments have shown that only large-brained social animals are able to recognise that a mirror shows a reflection of themselves. ^[13]

Animals that have shown they are able to use a mirror to study themselves:

• Asian elephants
• Bonobos
• Common chimpanzees
• Dolphins
• Orangutans
• Pigs
• Llamas

Unusual types of mirror

Other types of reflecting device are also called "mirrors". The mirror test is a measure of Self-awareness developed by Gordon Gallup Jr The Asian or Asiatic Elephant ( Elephas maximus) sometimes known by the name of one of its subspecies &ndash the Indian Elephant, is one of The Bonobo (bə'noʊboʊ Pan paniscus) until recently usually called the Pygmy Chimpanzee (and less often the Dwarf or Gracile Chimpanzee The Common Chimpanzee ( Pan troglodytes) also known as the Robust Chimpanzee, is a great ape. Dolphins are Marine mammals that are closely related to Whales and Porpoises There are almost forty species of dolphin in seventeen genera. The orangutans are two Species of great apes known for their intelligence long arms and reddish-brown hair Pigs, also called hogs or' swine', are Ungulates which have been domesticated as sources of food leather and similar products since ancient times The llama ( Lama glama) is a South American Camelid, widely used as a Pack animal by the Incas and other natives of the Andes For example metallic reflectors are used to reflect infrared light (such as in space heaters), or microwaves. Space heating is the Heating of a space usually enclosed such as a house or room Microwaves are electromagnetic waves with Wavelengths ranging from 1 mm to 1 m or frequencies between 0

An acoustic mirror is a passive device used to reflect and perhaps to focus sound waves. Kilnsea is a hamlet in the East Riding of Yorkshire, England, in an area known as Holderness. "Sound mirrors" redirects here For the album by Coldcut, see Sound Mirrors. An acoustic wave is a weak compression wave (meaning a small pressure change that moves at the Speed of sound. Acoustic mirrors were used for selective detection of sound waves, especially during World War 2. World War II, or the Second World War, (often abbreviated WWII) was a global military conflict which involved a majority of the world's nations, including They were used for detection of enemy aircraft prior to the development of radar. Radar is a system that uses electromagnetic waves to identify the range altitude direction or speed of both moving and fixed objects such as Aircraft, ships Acoustic mirrors are used for remote probing of the atmosphere; they can be used to form a narrow diffraction-limited beam. The resolution of an optical imaging system like a Microscope or Telescope or Camera can be limited by multiple factors like imperfections in the lenses or misalignment ^[14] They can also be used for underwater "imaging".

Active mirrors are mirrors that amplify the light they reflect. They are used to make disk lasers. A disk laser or active mirror (Fig1 is a type of Solid-state laser characterized by a heat sink and laser output that are realized on opposite sides of ^[15] The amplification is typically over a narrow range of wavelengths, and requires an external source of power.

An atomic mirror is a device which reflects matter waves. In Physics, an atomic mirror is a device which reflects neutral Atoms in the similar way as the conventional mirror reflects Visible light. In Physics, the de Broglie hypothesis (pronounced /brœj/ as French breuil close to "broy" is the statement that all Matter (any object has a Wave Usually, atomic mirrors work at grazing incidence. Angle of incidence is a measure of deviation of something from "straight on" for example in the approach of a ray to a surface or the angle Such a mirror 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. ^[16]

Cold mirrors are dielectric mirrors that reflect the entire visible light spectrum while efficiently transmitting infrared wavelengths. A cold mirror is a specialized Dielectric mirror, a Dichroic filter, that reflects the entire Visible light spectrum while very efficiently transmitting Conversely, hot mirrors reflect infrared light while allowing visible light to pass. A hot mirror is a specialized Dielectric mirror, a Dichroic filter, often employed to protect optical systems by reflecting Infrared light back into a light 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. A beam splitter is an optical device that splits a beam of Light in two

Corner reflectors use three flat mirrors to reflect light back towards its source. A corner reflector is a Retroreflector consisting of three mutually perpendicular intersecting flat surfaces which reflects Electromagnetic waves back towards the They are used for emergency location, and even laser ranging to the Moon. LIDAR ( Li ght D etection a nd R anging is an optical remote sensing technology that measures properties of scattered light to find range and/or

X-ray mirrors produce specular reflection of X-rays. X-radiation (composed of X-rays) is a form of Electromagnetic radiation. All known types work only at angles near grazing incidence, and only a small fraction of the rays are reflected. ^[17]

See also

• Anamorphosis
• Aranmula kannadi
• Bronze mirror
• Cold mirror and Hot mirror
• Deformable mirror
• Dielectric mirror
• Digital micromirror device
• Home decor
• Mirror armour (an oriental partial plate armour from polished metal mirrors)
• Mirror writing
• Perfect mirror
• Periscope
• Rear-view mirror
• Reflectivity
• Silvering
• TLV mirror — An ancient type of Chinese mirror from the Han Dynasty. Anamorphosis is a distorted projection or perspective requiring the viewer to use special devices or occupy a specific vantage point to reconstitute the image An Aranmula kannadi or Aranmula metal mirror is a special type of Mirror produced at Aranmula, a village in the state of Kerala in Bronze mirrors preceded the glass mirrors of today This type of mirror has been found by A cold mirror is a specialized Dielectric mirror, a Dichroic filter, that reflects the entire Visible light spectrum while very efficiently transmitting A hot mirror is a specialized Dielectric mirror, a Dichroic filter, often employed to protect optical systems by reflecting Infrared light back into a light Deformable mirror (DM represent the most convenient tool for Wavefront control and correction of optical Aberrations Deformable mirrors are used in combination with A dielectric mirror is a type of a Mirror composed of multiple thin layers of Dielectric material typically deposited on a substrate of Glass A Digital Micromirror Device, or DMD is an Optical Semiconductor that is the core of DLP projection Technology, and was Interior decoration or decor is the Art of decorating a room so that it is attractive easy to use and functions well with the existing Architecture Mirror armour (Зерцало Zertsalo which means a "mirror" Шар-айна Shar-ayna were айна ayna means a "mirror" too sometimes Mirror writing is formed by writing in the direction that is the reverse of the natural way for a given language such that the result is the Mirror image of normal writing A perfect mirror is a theoretical Mirror that reflects Light (and Electromagnetic radiation in general perfectly and doesn't transmit or absorb it A periscope is an instrument for observation from a concealed position In photometry and Heat transfer, reflectivity is the fraction of incident radiation reflected by a surface Silvering is the chemical process of coating Glass with a reflective substance A TLV mirror is a type of Bronze mirror that was popular during the Han Dynasty in China. The Han Dynasty ( 206 BC–220 AD followed the Qin Dynasty and preceded the Three Kingdoms in China.
• Venus effect

Notes

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). Sir Jonathan Wolfe Miller, CBE (born 21 July 1934) is a British Neurologist, Theatre and Opera director ISBN 0-300-07713-0 .
• The Mirror: A History, Sabine Melchior-Bonnet, Routledge, 2001, ISBN 0415924480

External links

• The Mirror: A History by Sabine Melchior-Bonnet at Google Books
• The Narcissus Syndrome Revisited by Yves Doré
• How Mirrors Are Made (video), Glass Association of North America]
• How Antique Mirrors can be reproduced
• Information on Bathroom Mirrors

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