Editing Mirror

{{Short description|Object that reflects an image}} 
{{other uses}}
{{Redirect|Looking glass|other uses|Looking Glass (disambiguation){{!}}Looking Glass}}
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{{Use dmy dates|date=January 2022}}
[[File:Mirror.jpg|thumb|A mirror reflecting the image of a [[vase]]]]
[[File:Enhanced aluminum coated first surface mirror on an optical flat.JPG|thumb|A [[first-surface mirror]] coated with aluminium and enhanced with [[dielectric]] coatings. The angle of the incident light (represented by both the light in the mirror and the shadow behind it) exactly matches the angle of reflection (the reflected light shining on the table).]]
[[File:WW1AcousticMirrorKilnsea(PaulGlazzard)Jan2007.jpg|thumb|{{convert|4.5|m|ft|adj=on}}-tall acoustic mirror near [[Kilnsea]] Grange, East Yorkshire, UK, from [[World War&nbsp;I]]. The mirror magnified the sound of approaching enemy [[Zeppelin]]s for a microphone placed at the [[Focus (geometry)|focal point]]. Sound waves are much longer than light waves, thus the object produces diffuse reflections in the visual spectrum.]]

A '''mirror''', also known as a '''looking glass''', is an object that [[Reflection (physics)|reflects]] an [[image]]. Light that bounces off a mirror forms an image of whatever is in front of it, which is then focused through the lens of the eye or a camera. Mirrors reverse the direction of light at an angle equal to its incidence. This allows the viewer to see themselves or objects behind them, or even objects that are at an angle from them but out of their field of view, such as around a corner. Natural mirrors have existed since [[Prehistory|prehistoric]] times, such as the surface of water, but people have been manufacturing mirrors out of a variety of materials for thousands of years, like stone, metals, and glass. In modern mirrors, metals like [[silver]] or [[aluminium]] are often used due to their high [[reflectivity]], applied as a thin coating on [[glass]] because of its naturally smooth and very [[Hardness (materials science)|hard]] surface.

A mirror is a [[Wave (physics)|wave]] reflector. [[Light]] consists of waves, and when light waves reflect from the flat surface of a mirror, those waves retain the same degree of curvature and [[Vergence (optics)|vergence]], in an equal yet opposite direction, as the original waves. This allows the waves to form an image when they are focused through a lens, just as if the waves had originated from the direction of the mirror. The light can also be pictured as [[Ray (optics)|rays]] (imaginary lines radiating from the light source, that are always perpendicular to the waves). These rays are reflected at an equal yet opposite angle from which they strike the mirror (incident light). This property, called [[specular reflection]], distinguishes a mirror from objects that [[Diffuse reflection|diffuse]] light, breaking up the wave and scattering it in many directions (such as flat-white paint). Thus, a mirror can be any surface in which the texture or roughness of the surface is smaller (smoother) than the [[wavelength]] of the waves.
 
When looking at a mirror, one will see a [[mirror image]] or reflected image of objects in the environment, formed by light emitted or scattered by them and reflected by the mirror towards one's eyes. This effect gives the illusion that those objects are behind the mirror, or (sometimes) [[real image|in front of it]]. When the surface is not flat, a mirror may behave like a reflecting [[lens]]. A [[plane mirror]] yields a real-looking undistorted image, while a [[curved mirror]] may distort, magnify, or reduce the image in various ways, while keeping the lines, [[Contrast (vision)|contrast]], [[Sharpness (visual)|sharpness]], colors, and other image properties intact.

A mirror is commonly used for inspecting oneself, such as during [[personal grooming]]; hence the old-fashioned name "looking glass".<ref name=camboldf/> This use, which dates from prehistory,<ref name=pend2004/> overlaps with uses in [[decorative arts|decoration]] and [[architecture]]. Mirrors are also used to view other items that are not directly visible because of obstructions; examples include [[rear-view mirror]]s in vehicles, [[curved mirror#Uses of convex mirrors|security mirrors]] in or around buildings, and [[mouth mirror|dentist's mirrors]]. Mirrors are also used in optical and scientific apparatus such as [[telescope]]s, [[laser]]s, [[camera]]s, [[periscope]]s, and industrial machinery.

According to [[superstition]]s breaking a mirror is said to bring seven years of [[List of bad luck signs|bad luck]].<ref>{{cite web|url=http://www.mirrorhistory.com/mirror-facts/broken-mirror/|title=Breaking a mirror - meaning of broken mirror|work=Mirror History|access-date=12 April 2017|archive-date=13 April 2017|archive-url=https://web.archive.org/web/20170413072419/http://www.mirrorhistory.com/mirror-facts/broken-mirror/|url-status=live}}</ref>

The terms "mirror" and "reflector" can be used for objects that reflect any other types of waves. An [[acoustic mirror]] reflects sound waves. Objects such as walls, ceilings, or natural rock-formations may produce [[echo]]s, and this tendency often becomes a problem in [[acoustical engineering]] when designing houses, auditoriums, or recording studios. Acoustic mirrors may be used for applications such as [[parabolic microphone]]s, [[atmosphere|atmospheric]] studies, [[sonar]], and [[seafloor mapping]].<ref name=U1/> An [[atomic mirror]] reflects [[matter waves]] and can be used for atomic [[interferometry]] and atomic [[holography]].

== History ==
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| image1 = Egypt, New Kingdom, Dynasty 18 - Caryatid Mirror - 1983.196 - Cleveland Museum of Art.tif
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| footer = '''Left:''' Bronze mirror, [[New Kingdom of Egypt]], [[Eighteenth dynasty of Egypt|Eighteenth Dynasty]], 1540–1296 BC, [[Cleveland Museum of Art]] (U.S.)<br />'''Right:''' seated woman holding a mirror; [[Ancient Greece|Ancient Greek]] Attic [[Red-figure pottery|red-figure]] [[lekythos]] by the [[Sabouroff Painter]], c. 470–460 BC, [[National Archaeological Museum, Athens]] (Greece)
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[[File:Naples National Archaeological Museum (14842094122).jpg|thumb|[[Roman art|Roman fresco]] of a woman fixing her hair using a mirror, from [[Stabiae]], Italy, 1st century AD]]
[[File:The Arnolfini Portrait, détail (2).jpg|thumb|Detail of the convex mirror from the [[Arnolfini portrait]], [[Bruges]], 1434 AD]]
[[File:Histoire de femme Gu Kai Zhi.jpg|thumb|'Adorning Oneself', detail from 'Admonitions of the Instructress to the Palace Ladies', [[Tang dynasty]] copy of an original by [[Chinese painting|Chinese painter]] [[Gu Kaizhi]], {{Circa|344–405 AD}}]]
[[File:Lady looking into mirror Belur Halebidu.jpg|thumb|A sculpture of a lady looking into a mirror, from [[Halebidu]], India, in the 12th century]]

===Prehistory===
The first mirrors used by humans were most likely pools of still water, or shiny stones.<ref>{{Cite book |last1=Melchior-Bonnet |first1=Sabine |title=The mirror: a history |last2=Jewett |first2=Katharina H. |last3=Delumeau |first3=Jean |date=2001 |publisher=Routledge |isbn=978-0-415-92447-4 |location=New York London}}</ref> The requirements for making a good mirror are a surface with a very high degree of [[Flat space|flatness]] (preferably but not necessarily with high [[reflectivity]]), and a [[surface roughness]] smaller than the wavelength of the light.

The earliest manufactured mirrors were pieces of polished stone such as [[obsidian]], a naturally occurring [[volcanic glass]].<ref name=fior2009/> Examples of obsidian mirrors found at [[Çatalhöyük]] in [[Anatolia]] (modern-day Turkey) have been dated to around 6000&nbsp;BCE.<ref name=enoch/> Mirrors of polished copper were crafted in [[Mesopotamia]] from 4000&nbsp;BCE,<ref name=enoch/> and in ancient Egypt from around 3000&nbsp;BCE.<ref name=stoc/> Polished stone mirrors from Central and South America date from around 2000&nbsp;BCE onwards.<ref name=enoch/>

===Bronze Age to Early Middle Ages===
{{main|Bronze mirror}}
By the [[Bronze Age]] most cultures were using mirrors made from polished discs of [[bronze]], [[copper]], [[silver]], or other metals.<ref name=fior2009/><ref name=whit2013/> The people of [[Kerma culture|Kerma]] in [[Nubia]] were skilled in the manufacturing of mirrors. Remains of their bronze [[kiln]]s have been found within the temple of Kerma.<ref>{{cite book| last = Bianchi| first = Robert Steven| title = Daily Life of the Nubians| year = 2004| publisher = Greenwood Publishing Group| isbn = 978-0-313-32501-4| page = 81 }}</ref> In China, [[bronze mirror]]s were manufactured from around 2000&nbsp;BC,<ref name="Ancient Chinese Bronze Mirrors">{{cite web |title=Ancient Chinese Bronze Mirrors |url=https://www.huntington.org/ancient-chinese-bronze-mirrors |website=The Huntington |publisher=The Huntington Library, Art Museum and Gardens |access-date=15 November 2020 |archive-date=17 November 2020 |archive-url=https://web.archive.org/web/20201117031015/https://www.huntington.org/ancient-chinese-bronze-mirrors |url-status=live }}</ref> some of the earliest bronze and copper examples being produced by the [[Qijia culture]]. Such metal mirrors remained the norm through to [[Greco-Roman]] Antiquity and throughout the [[Middle Ages]] in [[Europe]].<ref name=brit2009/> During the [[Roman Empire]] silver mirrors were in wide use by servants.<ref name=roma2019/>

[[Speculum metal]] is a highly reflective [[alloy]] of copper and [[tin]] that was used for mirrors until a couple of centuries ago.{{when|date=August 2022}}{{vague|date=August 2022}} Such mirrors may have originated in China and India.<ref name=need1974/> Mirrors of speculum metal or any precious metal were hard to produce and were only owned by the wealthy.<ref name=hopk1910/>

Common metal mirrors tarnished and required frequent polishing. Bronze mirrors had low reflectivity and poor [[color rendering]], and stone mirrors were much worse in this regard.<ref name=bonn2011/>{{rp|p.11}} These defects explain the [[New Testament]] reference in [[1 Corinthians 13]] to seeing "as in a mirror, darkly."

The [[Ancient Greece|Greek]] [[philosopher]] [[Socrates]] urged young people to look at themselves in mirrors so that, if they were beautiful, they would become worthy of their beauty, and if they were ugly, they would know how to hide their disgrace through learning.<ref name=bonn2011/>{{rp|p.106}}

[[Glass]] began to be used for mirrors in the 1st century [[Common Era|CE]], with the development of [[soda-lime glass]] and [[glass blowing]].<ref name=pulk1999/> The Roman scholar [[Pliny the Elder]] claims that artisans in [[Sidon]] (modern-day [[Lebanon]]) were producing glass mirrors coated with [[lead]] or [[gold leaf]] in the back. The metal provided good reflectivity, and the glass provided a smooth surface and protected the metal from scratches and tarnishing.<ref name=plin0077/><ref name=holl2009/><ref name=ande2008/><ref name=bonn2011/>{{rp|p.12}}<ref name=kels2007/> However, there is no archeological evidence of glass mirrors before the third century.<ref name=degy/>

These early glass mirrors were made by blowing a glass bubble, and then cutting off a small circular section from 10 to 20 [[centimetre|cm]] in diameter. Their surface was either concave or convex, and imperfections tended to distort the image. Lead-coated mirrors were very thin to prevent cracking by the heat of the molten metal.<ref name=bonn2011/>{{rp|p.10}} Due to the poor quality, high cost, and small size of glass mirrors, solid-metal mirrors (primarily of steel) remained in common use until the late nineteenth century.<ref name=bonn2011/>{{rp|p.13}}

Silver-coated metal mirrors were developed in China as early as 500 CE. The bare metal was coated with an [[amalgam (chemistry)|amalgam]], then heated until the [[mercury (element)|mercury]] boiled away.<ref name=rapp2009/>

===Middle Ages and Renaissance===
[[File:Johann Jacob Kirstein 001.JPG|thumb|An 18th century [[vermeil]] mirror in the [[Musée des Arts décoratifs, Strasbourg]]]]
[[File:Mirror with laquered back inlaid with 4 phoenixes holding ribbons in their mouths. Tang Dynasty. Eastern Xi'an city.jpg|thumb|A mirror with lacquered back inlaid with four phoenixes holding ribbons in their mouths during the [[Tang dynasty]] in eastern [[Xi'an]]]]
The evolution of glass mirrors in the [[Middle Ages]] followed improvements in [[glassmaking]] technology. Glassmakers in [[France]] made flat glass plates by blowing glass bubbles, spinning them rapidly to flatten them, and cutting rectangles out of them. A better method, developed in [[Germany]] and perfected in [[Venice]] by the 16th century, was to blow a cylinder of glass, cut off the ends, slice it along its length, and unroll it onto a flat hot plate.<ref name=bonn2011/>{{rp|p.11}} Venetian glassmakers also adopted [[lead glass]] for mirrors, because of its crystal-clarity and its easier workability.

During the early European [[Renaissance]], a [[gilding#Fire-gilding|fire-gilding]] technique developed to produce an even and highly reflective [[tin]] coating for glass mirrors. The back of the glass was coated with a tin-mercury amalgam, and the mercury was then evaporated by heating the piece. This process caused less [[thermal shock]] to the glass than the older molten-lead method.<ref name=bonn2011/>{{rp|p.16}} The date and location of the discovery is unknown, but by the 16th century Venice was a center of mirror production using this technique. These Venetian mirrors were up to {{convert|40|in|cm}} square.

For a century, Venice retained the monopoly of the tin amalgam technique. Venetian mirrors in richly decorated frames served as luxury decorations for palaces throughout Europe, and were very expensive. For example, in the late seventeenth century, the Countess de Fiesque was reported to have traded an entire wheat farm for a mirror, considering it a bargain.<ref name=hads1993/> However, by the end of that century the secret was leaked through industrial espionage. French workshops succeeded in large-scale industrialization of the process, eventually making mirrors affordable to the masses, in spite of the [[toxicity]] of mercury's vapor.<ref name=iriw2018/>

===Industrial Revolution===
{{Further|Industrial Revolution}}
The invention of the [[History of glass#Industrial production|ribbon machine]] in the late [[Industrial Revolution]] allowed modern glass panes to be produced in bulk.<ref name=bonn2011/> 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.

The invention of the [[silvering|silvered-glass]] mirror is credited to German chemist [[Justus von Liebig]] in 1835.<ref name=lieb185/> His [[Silvering#Silver|wet deposition]] 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.

===Contemporary technologies===
Mirrors are often produced by the wet deposition of silver, or sometimes nickel or chromium (the latter used most often in automotive mirrors) via [[electroplating]] directly onto the glass substrate.<ref name=mlink2014/>

Glass mirrors for optical instruments are usually produced by [[vacuum deposition]] methods. These techniques can be traced to observations in the 1920s and 1930s that metal was being ejected from [[electrode]]s in [[gas discharge lamp]]s and condensed on the glass walls forming a mirror-like coating. The phenomenon, called [[sputtering]], was developed into an industrial metal-coating method with the development of [[semiconductor]] technology in the 1970s.

A similar phenomenon had been observed with [[incandescent light bulbs]]: the metal in the hot filament would slowly [[sublimation (phase transition)|sublimate]] and condense on the bulb's walls. This phenomenon was developed into the method of [[evaporation (deposition)|evaporation coating]] by Pohl and Pringsheim in 1912. [[John D. Strong]] used evaporation coating to make the first [[aluminium]]-coated telescope mirrors in the 1930s.<ref name=matt2004/> The first [[dielectric mirror]] was created in 1937 by Auwarter using evaporated [[rhodium]].<ref name=pulk1999/>

The metal coating of glass mirrors is usually protected from abrasion and corrosion by a layer of paint applied over it. Mirrors for optical instruments often have the metal layer on the front face, so that the light does not have to cross the glass twice. In these mirrors, the metal may be protected by a thin transparent coating of a non-metallic ([[dielectric]]) material. The first metallic mirror to be enhanced with a dielectric coating of [[silicon dioxide]] was created by Hass in 1937. In 1939 at the [[Schott Glass]] company, Walter Geffcken invented the first dielectric mirrors to use multilayer coatings.<ref name=pulk1999/>

===Burning mirrors===
The [[Ancient Greece|Greek]] in [[Classical Antiquity]] were familiar with the use of mirrors to concentrate light. [[Parabolic mirror]]s were described and studied by the mathematician [[Diocles (mathematician)|Diocles]] in his work ''On Burning Mirrors''.<ref name=fried2001/> [[Ptolemy]] conducted a number of experiments with curved polished iron mirrors,<ref name=pend2004/>{{rp|p.64}} and discussed plane, convex spherical, and concave spherical mirrors in his ''Optics''.<ref name=mark1996/>

Parabolic mirrors were also described by the [[Caliphate]] mathematician [[Ibn Sahl (mathematician)|Ibn Sahl]] in the tenth century.<ref name=rash1990/>

==Types of mirrors==
[[File:UniversumUNAM27.JPG|thumb|A curved mirror at the [[Universum (UNAM)|Universum museum]] in Mexico City. The image splits between the convex and concave curves.]]
[[File:Mirror statue - Győr, 2015.10.31.JPG|thumb|A large convex mirror. Distortions in the image increase with the viewing distance.]]
Mirrors can be classified in many ways; including by shape, support, reflective materials, manufacturing methods, and intended application.

===By shape===
Typical mirror shapes are [[plane mirror|planar]] and [[Curved mirror|curved]] mirrors.

The surface of curved mirrors is often a part of a [[sphere]]. Mirrors that are meant to precisely concentrate parallel rays of light into a point are usually made in the shape of a [[paraboloid of revolution]] instead; they are used in telescopes (from radio waves to X-rays), in antennas to communicate with [[broadcast satellite]]s, and in [[solar furnace]]s. A [[segmented mirror]], consisting of multiple flat or curved mirrors, properly placed and oriented, may be used instead.

Mirrors that are intended to concentrate sunlight onto a long pipe may be a [[circular cylinder]] or of a [[parabolic cylinder]].<ref>{{cite web |title=Linear Concentrator System Concentrating Solar-Thermal Power Basics |url=https://www.energy.gov/eere/solar/linear-concentrator-system-concentrating-solar-thermal-power-basics |website=Office of Energy Efficiency & Renewable Energy |publisher=US Dept. Of Energy |access-date=23 January 2023 |archive-date=23 January 2023 |archive-url=https://web.archive.org/web/20230123062745/https://www.energy.gov/eere/solar/linear-concentrator-system-concentrating-solar-thermal-power-basics |url-status=live }}</ref>

===By structural material===
The most common structural material for mirrors is glass, due to its transparency, ease of fabrication, rigidity, hardness, and ability to take a smooth finish.

====Back-silvered mirrors====
The most common mirrors consist of a plate of transparent glass, with a thin reflective layer on the back (the side opposite to the incident and reflected light) backed by a coating that protects that layer against abrasion, tarnishing, and [[corrosion]]. The glass is usually soda-lime glass, but lead glass may be used for decorative effects, and other transparent materials may be used for specific applications.<ref>{{Cite web |last=Lowder |first=Stephanie |date=2015-01-23 |title=The History of Mirror: Through A Glass, Darkly |url=https://www.furniturelibrary.com/mirror-glass-darkly/ |access-date=2025-04-24 |website=Bienenstock Furniture Library |language=en-US}}</ref>

A plate of transparent [[plastic]] may be used instead of glass, for lighter weight or impact resistance. Alternatively, a flexible transparent plastic film may be bonded to the front and/or back surface of the mirror, to prevent injuries in case the mirror is broken. Lettering or decorative designs may be printed on the front face of the glass, or formed on the reflective layer. The front surface may have an [[anti-reflection coating]].<ref>{{Cite journal |last1=Yamada |first1=Y. |last2=Kitamura |first2=S. |last3=Miura |first3=M. |last4=Yoshimura |first4=K. |date=2015-10-01 |title=Improving the optical properties of switchable mirrors based on Mg–Y alloy using antireflection coatings |url=https://linkinghub.elsevier.com/retrieve/pii/S0927024815002755 |journal=Solar Energy Materials and Solar Cells |volume=141 |pages=337–340 |doi=10.1016/j.solmat.2015.06.006 |bibcode=2015SEMSC.141..337Y |issn=0927-0248|url-access=subscription }}</ref>

====Front-silvered mirrors====
Mirrors which are reflective on the front surface (the same side of the incident and reflected light) may be made of any rigid material.<ref name=scha2011/> The supporting material does not necessarily need to be transparent, but telescope mirrors often use glass anyway. Often a protective transparent coating is added on top of the reflecting layer, to protect it against abrasion, tarnishing, and corrosion, or to absorb certain wavelengths.<ref>{{cite journal |last1=Bulkin |first1=Pavel |last2=Gaiaschi |first2=Sofia |last3=Chapon |first3=Patrick |last4=Daineka |first4=Dmitri |last5=Kundikova |first5=Natalya |title=Protective coatings for front surface silver mirrors by atomic layer deposition |url=https://opg.optica.org/oe/fulltext.cfm?uri=oe-28-11-15753&id=431675 |journal=Optics Express |year=2020 |volume=28 |issue=11 |pages=15753–15760 |publisher=Optica Publishing Group |doi=10.1364/OE.388546 |pmid=32549412 |arxiv=1912.01000 |bibcode=2020OExpr..2815753B |s2cid=208526874 |access-date=23 January 2023}}</ref>

====Flexible mirrors====
Thin flexible plastic mirrors are sometimes used for safety, since they cannot shatter or produce sharp flakes. Their flatness is achieved by stretching them on a rigid frame. These usually consist of a layer of evaporated aluminium between two thin layers of transparent plastic.<ref>{{Cite journal |last1=Arias |first1=Nathaly |last2=Jaramillo |first2=Franklin |date=2020-03-01 |title=Highly reflective aluminum films on polycarbonate substrates by physical vapor deposition |url=https://linkinghub.elsevier.com/retrieve/pii/S0169433219334129 |journal=Applied Surface Science |volume=505 |pages=144596 |doi=10.1016/j.apsusc.2019.144596 |bibcode=2020ApSS..50544596A |issn=0169-4332|url-access=subscription }}</ref><ref>{{Cite journal |last1=Azzam |first1=Yosry A. |last2=Abd El Hameed |first2=Afaf M. |last3=El-Tokhy |first3=Fatma S. |last4=Ismail |first4=Mohamed |last5=El_harony |first5=M. |last6=Sharaf |first6=S. M. |date=2015-01-22 |title=Investigation and treatment of the aluminizing process for mirrors of astronomical telescopes and optical instruments of space vehicles |url=https://linkinghub.elsevier.com/retrieve/pii/S1359431114008862 |journal=Applied Thermal Engineering |volume=75 |pages=856–866 |doi=10.1016/j.applthermaleng.2014.10.015 |bibcode=2015AppTE..75..856A |issn=1359-4311|url-access=subscription }}</ref>

===By reflective material===
[[File:Dielectric mirror diagram.svg|thumb|A dielectric mirror-stack works on the principle of [[thin-film interference]]. Each layer has a different [[refractive index]], allowing each interface to produce a small amount of reflection. When the thickness of the layers is proportional to the chosen wavelength, the multiple reflections [[constructive interference|constructively interfere]]. Stacks may consist of a few to hundreds of individual coats.]]
[[File:Hot mirror for a camera.jpg|thumb|A hot mirror used in a camera to reduce red eye]]

In common mirrors, the reflective layer is usually some metal like silver, tin, [[nickel]], or [[chromium]], deposited by a wet process; or aluminium,<ref name=mlink2014/><ref name=saun2004/> deposited by sputtering or evaporation in vacuum. The reflective layer may also be made of one or more layers of transparent materials with suitable [[index of refraction|indices of refraction]].

The structural material may be a metal, in which case the reflecting layer may be just the surface of the same. Metal concave dishes are often used to reflect infrared light (such as in [[space heater]]s) or [[microwave]]s (as in satellite TV antennas). [[Liquid-mirror telescope|Liquid metal telescopes]] use a surface of liquid metal such as mercury.

Mirrors that reflect only part of the light, while transmitting some of the rest, can be made with very thin metal layers or suitable combinations of dielectric layers. They are typically used as [[beamsplitter]]s. A [[dichroic mirror]], in particular, has surface that reflects certain wavelengths of light, while letting other wavelengths pass through. A [[cold mirror]] is a dichroic mirror that efficiently reflects the entire [[visible light spectrum]] while transmitting [[infrared]] wavelengths. A [[hot mirror]] is the opposite: it reflects infrared light while transmitting visible light. Dichroic mirrors are often used as filters to remove undesired components of the light in cameras and measuring instruments.

In [[X-ray optics|X-ray telescopes]], the [[X-ray]]s reflect off a highly precise metal surface at almost grazing angles, and only a small fraction of the rays are reflected.<ref name=pro00/> In [[flying relativistic mirrors]] conceived for [[X-ray laser]]s, the reflecting surface is a spherical [[shockwave]] (wake wave) created in a low-density [[plasma (physics)|plasma]] by a very intense laser-pulse, and moving at an extremely high velocity.<ref name=lewis2008/>

====Nonlinear optical mirrors====
A [[nonlinear optics#Optical phase conjugation|phase-conjugating mirror]] uses [[nonlinear optics]] to reverse the phase difference between incident beams. Such mirrors may be used, for example, for coherent beam combination. The useful applications are self-guiding of laser beams and correction of atmospheric distortions in imaging systems.<ref name=okul1980/><ref name=okul2014/><ref name=boyd1997/>

==Physical principles==
[[File:Mirror reflecting light waves.png|thumb|A mirror reflects light waves to the observer, preserving the wave's curvature and divergence, to form an image when focused through the lens of the eye. The angle of the impinging wave, as it traverses the mirror's surface, matches the angle of the reflected wave.]]
When a sufficiently narrow beam of light is reflected at a point of a surface, the [[surface normal|surface's normal direction]] <math>\vec n</math> will be the bisector of the angle formed by the two beams at that point. That is, the [[direction vector]] <math>\vec u</math> towards the incident beams's source, the normal vector <math>\vec n</math>, and direction vector <math>\vec v</math> of the reflected beam will be [[coplanarity|coplanar]], and the angle between <math>\vec n</math> and <math>\vec v</math> will be equal to the [[angle of incidence (optics)|angle of incidence]] between <math>\vec n</math> and <math>\vec u</math>, but of opposite sign.<ref name=katz2016/>

This property can be explained by the physics of an [[electromagnetic wave|electromagnetic]] [[plane wave]] that is incident to a flat surface that is [[electrical conductance|electrically conductive]] or where the [[speed of light]] changes abruptly, as between two materials with different indices of refraction.

* When [[parallel (geometry)|parallel]] beams of light are reflected on a plane surface, the reflected rays will be parallel too.
* If the reflecting surface is concave, the reflected beams will be [[Vergence (optics)|convergent]], at least to some extent and for some distance from the surface.
* A convex mirror, on the other hand, will reflect parallel rays towards [[divergence|divergent]] directions.

More specifically, a concave parabolic mirror (whose surface is a part of a paraboloid of revolution) will reflect rays that are parallel to its [[surface of revolution|axis]] into rays that pass through its [[focus (optics)|focus]]. Conversely, a parabolic concave mirror will reflect any ray that comes from its focus towards a direction parallel to its axis. If a concave mirror surface is a part of a [[ellipsoid|prolate ellipsoid]], it will reflect any ray coming from one focus toward the other focus.<ref name=katz2016/>

A convex parabolic mirror, on the other hand, will reflect rays that are parallel to its axis into rays that seem to emanate from the focus of the surface, behind the mirror. Conversely, it will reflect incoming rays that converge toward that point into rays that are parallel to the axis. A convex mirror that is part of a prolate ellipsoid will reflect rays that converge towards one focus into divergent rays that seem to emanate from the other focus.<ref name=katz2016/>

Spherical mirrors do not reflect parallel rays to rays that converge to or diverge from a single point, or vice versa, due to [[spherical aberration]]. However, a spherical mirror whose diameter is sufficiently small compared to the sphere's radius will behave very similarly to a parabolic mirror whose axis goes through the mirror's center and the center of that sphere; so that spherical mirrors can substitute for parabolic ones in many applications.<ref name=katz2016/>

A similar aberration occurs with parabolic mirrors when the incident rays are parallel among themselves but not parallel to the mirror's axis, or are divergent from a point that is not the focus – as when trying to form an image of an object that is near the mirror or spans a wide angle as seen from it. However, this aberration can be sufficiently small if the object image is sufficiently far from the mirror and spans a sufficiently small angle around its axis.<ref name=katz2016/>

===Mirror images===
{{Main|Mirror image}}
[[File:Lake O Hara Early Morning Reflection (173874897).jpeg|thumb|A mirror reverses an image in the direction of the normal [[Angle of incidence (optics)|angle of incidence]]. When the surface is at a 90°, horizontal angle from the object, the image appears inverted 180° along the vertical (right and left remain on the correct sides, but the image appears upside down), because the normal angle of incidence points down vertically toward the water.]]
[[File:Mirror virtual image.png|thumb|A mirror reflects a real image (blue) back to the observer (red), forming a virtual image; a perceptual illusion that objects in the image are behind the mirror's surface and facing the opposite direction (purple). The arrows indicate the direction of the real and perceived images, and the reversal is analogous to viewing a movie with the film facing backwards, except the "screen" is the viewer's retina.]]

Mirrors reflect an image to the observer. However, unlike a projected image on a screen, an image does not actually exist on the surface of the mirror. For example, when two people look at each other in a mirror, both see different images on the same surface. When the light waves converge through the lens of the eye they interfere with each other to form the image on the surface of the [[retina]], and since both viewers see waves coming from different directions, each sees a different image in the same mirror. Thus, the images observed in a mirror depend upon the angle of the mirror with respect to the eye. The angle between the object and the observer is always twice the angle between the eye and the normal, or the direction perpendicular to the surface. This allows animals with [[binocular vision]] to see the reflected image with [[depth perception]] and in three dimensions.

The mirror forms a ''virtual image'' of whatever is in the opposite angle from the viewer, meaning that objects in the image appear to exist in a direct [[line of sight]]—behind the surface of the mirror—at an equal distance from their position in front of the mirror. Objects behind the observer, or between the observer and the mirror, are reflected back to the observer without any actual change in orientation; the light waves are simply reversed in a direction perpendicular to the mirror. However, when viewer is facing the object and the mirror is at an angle between them, the image appears inverted 180° along the direction of the angle.<ref name="ReferenceA">''Mastering Physics for ITT-JEE, Volume 2'' By S. Chand & Co. 2012 Er. Rakesh Rathi Page 273--276</ref>

Objects viewed in a (plane) mirror will appear laterally inverted (e.g., if one raises one's right hand, the image's left hand will appear to go up in the mirror), but not vertically inverted (in the image a person's head still appears above their body).<ref name=lard1845/> However, a mirror does not actually "swap" left and right any more than it swaps top and bottom. A mirror swaps front and back. To be precise, it reverses the object in the direction perpendicular to the mirror surface (the normal), turning the three dimensional image inside out (the way a glove stripped off the hand can be turned inside out, turning a left-hand glove into a right-hand glove or vice versa). When a person raises their left hand, the actual left hand raises in the mirror, but gives the illusion of a right hand raising because the imaginary person in the mirror is literally inside-out, hand and all. If the person stands side-on to a mirror, the mirror really does reverse left and right hands, that is, objects that are physically closer to the mirror always appear closer in the virtual image, and objects farther from the surface always appear symmetrically farther away regardless of angle.

Looking at an image of oneself with the front-back axis flipped results in the perception of an image with its left-right axis flipped. When reflected in the mirror, a person's right hand remains directly opposite their real right hand, but it is perceived by the mind as the left hand in the image. When a person looks into a mirror, the image is actually front-back reversed (inside-out), which is an effect similar to the [[hollow-mask illusion]]. Notice that a mirror image is fundamentally different from the object (inside-out) and cannot be reproduced by simply rotating the object. An object and its mirror image are said to be [[chiral]].

For things that may be considered as two-dimensional objects (like text), front-back reversal cannot usually explain the observed reversal. An image is a two-dimensional representation of a three-dimensional space, and because it exists in a two-dimensional [[Focal plane|plane]], an image can be viewed from front or back. In the same way that text on a piece of paper appears reversed if held up to a light and viewed from behind, text held facing a mirror will appear reversed, because the image of the text is still facing away from the observer. Another way to understand the reversals observed in images of objects that are effectively two-dimensional is that the inversion of left and right in a mirror is due to the way human beings perceive their surroundings. A person's reflection in a mirror appears to be a real person facing them, but for that person to really face themselves (i.e.: twins) one would have to physically turn and face the other, causing an actual swapping of right and left. A mirror causes an illusion of left-right reversal because left and right were ''not'' swapped when the image appears to have turned around to face the viewer. The viewer's [[egocentric navigation]] (left and right with respect to the observer's point of view; i.e.: "my left...") is unconsciously replaced with their [[allocentric navigation]] (left and right as it relates another's point of view; "...your right") when processing the virtual image of the apparent person behind the mirror. Likewise, text viewed in a mirror would have to be physically turned around, facing the observer and away from the surface, actually swapping left and right, to be read in the mirror.<ref name="ReferenceA"/>

==Optical properties==
===Reflectivity===
[[File:Four mirrors - dielectric aluminum silver and chrome.jpg|thumb|Four different mirrors, showing the difference in reflectivity. Clockwise from upper left: dielectric (80%), aluminium (85%), chrome (25%), and enhanced silver (99.9%). All are first-surface mirrors except the chrome mirror. The dielectric mirror reflects yellow light from the first-surface, but acts like an [[antireflection coating]] to purple light, thus produced a ghost reflection of the lightbulb from the second-surface.]]
[[File:Image-Metal-reflectance.png|thumb|Spectral [[reflectance]] curves for [[aluminium]] (Al), [[silver]] (Ag), and [[gold]] (Au) metal mirrors at normal incidence.]]
The reflectivity of a mirror is determined by the percentage of reflected light per the total of the incident light. The reflectivity may vary with wavelength. All or a portion of the light not reflected is [[Absorption (electromagnetic radiation)|absorbed]] by the mirror, while in some cases a portion may also transmit through. Although some small portion of the light will be absorbed by the coating, the reflectivity is usually higher for first-surface mirrors, eliminating both reflection and absorption losses from the substrate.

The reflectivity is often determined by the type and thickness of the coating. When the thickness of the coating is sufficient to prevent transmission, all of the losses occur due to absorption. Aluminium is harder and more resistant to tarnishing than silver, and will reflect 85 to 90% of the light in the visible to near-ultraviolet range, but experiences a drop in its reflectance between 800 and 900&nbsp;nm. Gold is very soft and easily scratched, but does not tarnish. Gold is greater than 96% reflective to near and far-infrared light between 800 and 12000&nbsp;nm, but poorly reflects visible light with wavelengths shorter than 600&nbsp;nm (yellow). Silver is expensive, soft, and quickly tarnishes, but has the highest reflectivity in the visual to near-infrared of any metal. Silver can reflect up to 98 or 99% of light to wavelengths as long as 2000&nbsp;nm, but loses nearly all reflectivity at wavelengths shorter than 350&nbsp;nm.

Dielectric mirrors can reflect greater than 99.99% of light, but only for a narrow range of wavelengths, ranging from a bandwidth of only 10&nbsp;nm to as wide as 100&nbsp;nm for [[tunable laser]]s. However, dielectric coatings can also enhance the reflectivity of metallic coatings and protect them from scratching or tarnishing. Dielectric materials are typically very hard and relatively cheap, however the number of coats needed generally makes it an expensive process. In mirrors with low tolerances, the coating thickness may be reduced to save cost, and simply covered with paint to absorb transmission.<ref name=walk1998/>

===Surface quality===
[[File:Mirror distortion and artifacts due to flatness errors.png|thumb|Flatness errors, like rippled dunes across the surface, produced these artifacts, distortion, and low image quality in the [[far field]] reflection of a household mirror.]]
Surface quality, or surface accuracy, measures the deviations from a perfect, ideal surface shape. Increasing the surface quality reduces distortion, artifacts, and [[Aberration (optics)|aberration]] in images, and helps increase [[Coherence (physics)|coherence]], [[collimation]], and reduce unwanted [[beam divergence|divergence]] in beams. For plane mirrors, this is often described in terms of [[Flatness (manufacturing)|flatness]], while other surface shapes are compared to an ideal shape. The surface quality is typically measured with items like [[interferometer]]s or [[optical flat]]s, and are usually measured in wavelengths of light (λ). These deviations can be much larger or much smaller than the surface roughness. A normal household-mirror made with [[float glass]] may have flatness tolerances as low as 9–14λ per inch (25.4&nbsp;mm), equating to a deviation of 5600 through 8800 [[nanometer]]s from perfect flatness. Precision ground and polished mirrors intended for lasers or telescopes may have tolerances as high as λ/50 (1/50 of the wavelength of the light, or around 12&nbsp;nm) across the entire surface.<ref name=cheng2009/><ref name=walk1998/> The surface quality can be affected by factors such as temperature changes, internal stress in the substrate, or even bending effects that occur when combining materials with different coefficients of [[thermal expansion]], similar to a [[bimetallic strip]].<ref name=leon2006/>

===Surface roughness===
[[Surface roughness]] describes the texture of the surface, often in terms of the depth of the microscopic scratches left by the polishing operations. Surface roughness determines how much of the reflection is specular and how much diffuses, controlling how clear or cloudy the image will be.

For perfectly specular reflection, the surface roughness must be kept smaller than the wavelength of the light. Microwaves, which sometimes have a wavelength greater than an inch (~25&nbsp;mm) can reflect specularly off a metal screen-door, continental ice-sheets, or desert sand, while visible light, having wavelengths of only a few hundred nanometers (a few hundred-thousandths of an inch), must meet a very smooth surface to produce specular reflection. For wavelengths that are approaching or are even shorter than the [[Atomic radius|diameter of the atoms]], such as [[X-ray]]s, specular reflection can only be produced by surfaces that are at a [[grazing incidence]] from the rays.

Surface roughness is typically measured in [[micron]]s, wavelength, or [[Sandpaper#Grit size table|grit size]], with ~80,000–100,000&nbsp;grit or ~½λ–¼λ being "optical quality".<ref name=duzg2011/><ref name=walk1998/><ref name=warn/>

===Transmissivity===
[[File:Laser dielectric output coupler centered @ 550nm.png|thumb|A dielectric, laser output-coupler that is 75–80% reflective between 500 and 600 nm, on a 3° [[wedge prism]] made of [[quartz glass]]. Left: The mirror is highly reflective to yellow and green but highly transmissive to red and blue. Right: The mirror transmits 25% of the 589 nm laser light. Because the smoke particles [[Diffraction|diffract]] more light than they reflect, the beam appears much brighter when reflecting back toward the observer.]]
Transmissivity is determined by the percentage of light transmitted per the incident light. Transmissivity is usually the same from both first and second surfaces. The combined transmitted and reflected light, subtracted from the incident light, measures the amount absorbed by both the coating and substrate. For transmissive mirrors, such as one-way mirrors, [[beam splitter]]s, or laser [[output coupler]]s, the transmissivity of the mirror is an important consideration. The transmissivity of metallic coatings are often determined by their thickness. For precision beam-splitters or output couplers, the thickness of the coating must be kept at very high tolerances to transmit the proper amount of light. For dielectric mirrors, the thickness of the coat must always be kept to high tolerances, but it is often more the number of individual coats that determine the transmissivity. For the substrate, the material used must also have good transmissivity to the chosen wavelengths. Glass is a suitable substrate for most visible-light applications, but other substrates such as [[zinc selenide]] or [[synthetic sapphire]] may be used for infrared or ultraviolet wavelengths.<ref name=greav1989/>{{rp|p.104–108}}

===Wedge===
Wedge errors are caused by the deviation of the surfaces from perfect parallelism. An [[optical wedge]] is the angle formed between two plane-surfaces (or between the principle planes of curved surfaces) due to manufacturing errors or limitations, causing one edge of the mirror to be slightly thicker than the other. Nearly all mirrors and optics with parallel faces have some slight degree of wedge, which is usually measured in [[second of arc|seconds]] or [[minutes of arc]]. For first-surface mirrors, wedges can introduce alignment deviations in mounting hardware. For second-surface or transmissive mirrors, wedges can have a prismatic effect on the light, deviating its trajectory or, to a very slight degree, its color, causing [[chromatic aberration|chromatic]] and other forms of [[Optical aberration|aberration]]. In some instances, a slight wedge is desirable, such as in certain laser systems where stray reflections from the uncoated surface are better dispersed than reflected back through the medium.<ref name=walk1998/><ref name=klei1989/>

===Surface defects===
Surface defects are small-scale, discontinuous imperfections in the surface smoothness. Surface defects are larger (in some cases much larger) than the surface roughness, but only affect small, localized portions of the entire surface. These are typically found as scratches, digs, pits (often from bubbles in the glass), sleeks (scratches from prior, larger grit polishing operations that were not fully removed by subsequent polishing grits), edge chips, or blemishes in the coating. These defects are often an unavoidable side-effect of manufacturing limitations, both in cost and machine precision. If kept low enough, in most applications these defects will rarely have any adverse effect, unless the surface is located at an image plane where they will show up directly. For applications that require extremely low scattering of light, extremely high reflectance, or low absorption due to high energy levels that could destroy the mirror, such as lasers or [[Fabry-Perot interferometer]]s, the surface defects must be kept to a minimum.<ref name=azop2016/>

== Manufacturing ==
[[File:Hubble mirror polishing.jpg|thumb|Polishing the primary mirror for the [[Hubble Space Telescope]]. A deviation in the surface quality of approximately 4λ resulted in poor images initially, which was eventually compensated for using [[Corrective Optics Space Telescope Axial Replacement|corrective optics]].]]

Mirrors are usually manufactured by either polishing a naturally reflective material, such as speculum metal, or by applying a [[silvering|reflective coating]] to a suitable polished [[substrate (materials science)|substrate]].<ref name=lanz2012/>

In some applications, generally those that are cost-sensitive or that require great durability, such as for mounting in a prison cell, mirrors may be made from a single, bulk material such as polished metal. However, metals consist of small crystals (grains) separated by grain boundaries that may prevent the surface from attaining optical smoothness and uniform reflectivity.<ref name=pulk1999/>{{rp|p.2,8}}

===Coating===
====Silvering====
{{main|silvering}}
The coating of glass with a reflective layer of a metal is generally called "[[silvering]]", even though the metal may not be silver. Currently the main processes are [[electroplating]], "wet" [[electroless plating|chemical deposition]], and [[vacuum deposition]].<ref name=pulk1999/> Front-coated metal mirrors achieve reflectivities of 90–95% when new.

====Dielectric coating====
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 99.997% over a limited range of wavelengths. Because they are often chemically stable and do not conduct electricity, dielectric coatings are almost always applied by methods of vacuum deposition, and most commonly by evaporation deposition. Because the coatings are usually transparent, absorption losses are negligible. Unlike with metals, the reflectivity of the individual dielectric-coatings is a function of [[Snell's law]] known as the [[Fresnel equations]], determined by the difference in [[refractive index]] between layers. Therefore, the thickness and index of the coatings can be adjusted to be centered on any wavelength. Vacuum deposition can be achieved in a number of ways, including sputtering, evaporation deposition, arc deposition, reactive-gas deposition, and ion plating, among many others.<ref name=pulk1999/>{{rp|p.103,107}}

===Shaping and polishing===
====Tolerances====
Mirrors can be manufactured to a wide range of [[engineering tolerance]]s, including [[reflectivity]], surface quality, [[surface roughness]], or [[Transmittance|transmissivity]], depending on the desired application. These tolerances can range from wide, such as found in a normal household-mirror, to extremely narrow, like those used in lasers or telescopes. Tightening the tolerances allows better and more precise imaging or beam transmission over longer distances. In imaging systems this can help reduce anomalies ([[Artifact (error)|artifacts]]), distortion or blur, but at a much higher cost. Where viewing distances are relatively close or high precision is not a concern, wider tolerances can be used to make effective mirrors at affordable costs.

== Applications ==
[[File:Jekyll.and.Hyde.Ch10.Drawing2.jpg|thumb|upright|A cheval glass]]
[[File:mirror.globe.arp.500pix.jpg|thumb|upright|Reflections in a spherical convex mirror. The photographer is seen at top right.]]
[[File:In Car Micheal Fitzgerald Cork Racing.jpg|thumb|A side-mirror on a [[racing car]]]]
[[File:Memphis in Front of Me, Arkansas in Back of Me.jpg|thumb|Rear-view mirror]]


=== Personal grooming ===
Mirrors are commonly used as aids to [[personal grooming]].<ref name=schr1969/> They may range from small sizes (portable), to full body sized; they may be handheld, mobile, fixed or adjustable. A classic example of an adjustable mirror is the [[cheval glass]], which the user can tilt.

=== Safety and easier viewing ===
;Convex mirrors
[[File:-94wiki.jpg|thumb|A convex mirror in a [[parking garage]]]]
Convex mirrors provide a wider [[field of view]] than flat mirrors,<ref name=king2000/> and are often used on vehicles,<ref name=ushw1979/> especially large trucks, to minimize [[Blind spot (automobile)|blind spots]]. They are sometimes placed at [[road junction]]s, and at 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.<ref>{{Cite web |title=Why are Convex Mirrors Used in Shops  |url=https://www.insight-security.com/why-are-convex-mirrors-used-in-shops |access-date=2024-09-17 |website=insight-security.com}}</ref> Convex mirrors as decoration are used in interior design to provide a predominantly experiential effect.<ref name=charm2016/>

;[[Mouth mirror]]s or "dental mirrors"
:Dentists use mouth mirrors or "dental mirrors" to allow indirect vision and lighting within the mouth. Their reflective surfaces may be either flat or curved.<ref name=ande2000/> Mouth mirrors are also commonly used by [[mechanic]]s to allow vision in tight spaces and around corners in equipment.
;[[Rear-view mirror]]s
: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.<ref name=kali/> On rear-view sunglasses, the left end of the left glass and the right end of the right glass work as mirrors.

=== One-way mirrors and windows ===
{{Main|One-way mirror}}
;One-way mirrors
:One-way mirrors (also called two-way mirrors) work by overwhelming dim transmitted light with bright reflected light.<ref name=twow2012/> 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]].{{Citation needed|reason=A common-sense explanation is not sufficient. A source that discusses this more in depth is needed.|date=November 2015}}
;One-way windows
: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 name=mung1999/><ref name=rayle1901/> [[Faraday isolator|Optical isolators]] are one-way devices that are commonly used with lasers.

=== Signalling ===
{{Main|Heliograph}}
With the sun as the 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 {{convert|60|km}} on a clear day. [[Indigenous peoples of the Americas|Native American]] tribes and numerous [[military|militaries]] used this technique to transmit information between distant outposts.

Mirrors can also be used to attract the attention of [[search-and-rescue]] parties. Specialized types of mirrors are available and are often included in military [[survival kit]]s.<ref>{{Cite book|last=Fears|first=J. Wayne|url=https://books.google.com/books?id=tF2CDwAAQBAJ|title=The Pocket Outdoor Survival Guide: The Ultimate Guide for Short-Term Survival|date=14 February 2011|publisher=Simon and Schuster|isbn=978-1-62636-680-0|language=en|quote=Most survival experts consider the signal mirror to be one of the best signal devices available.|access-date=25 August 2020|archive-date=18 January 2023|archive-url=https://web.archive.org/web/20230118083411/https://books.google.com/books?id=tF2CDwAAQBAJ|url-status=live}}</ref>

=== Technology ===

==== Televisions and projectors ====

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).

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.

Large mirrors are used in rear-projection televisions. Light (for example from a DLP as discussed above) is "folded" by one or more mirrors so that the television set is compact.

==== Optical discs ====
[[Optical disc]]s are modified mirrors which encode binary data as a series of physical pits and lands on an inner layer between the metal backing and outer plastic surface. The data is read and decoded by observing distortions in a reflected laser beam caused by the physical variations in the inner layer. Optical discs typically use aluminum backing like conventional mirrors, though ones with silver and [[Gold compact disc|gold]] backings also exist.

==== Solar power ====
[[File:Parabolic trough near Harper Lake in California front and back.jpg|thumb|Parabolic troughs near [[Harper Lake]] in [[California]]]]
Mirrors are integral parts of a [[solar power]] plant. The one shown in the adjacent picture uses [[concentrated solar power]] from an array of [[parabolic trough]]s.<ref name=pale2015/>

==== Instruments ====
{{See also|Mirror support cell}}
[[File:E-ELT mirror segments under test.jpg|thumb|[[E-ELT]] mirror segments under test]]
[[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.
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]].
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 air. ''Front silvered'' mirrors have to be resurfaced occasionally to maintain 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 name=boba2014/>

[[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 name=eso2013/>]]

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.

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, aluminium 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.

[[File:Dielectric laser mirror from a dye laser.JPG|thumb|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.]]
[[File:Laserr mirror from a dye laser for use with rhodamine.jpg|thumb |A dielectric mirror used in [[tunable laser]]s. With a center wavelength of 600 nm and bandwidth of 100 nm, the coating is totally reflective to the orange construction paper, but only reflects the reddish hues from the blue paper.]]
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 &gt;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.

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.

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.

Simple [[periscope]]s use mirrors.

==== Face-to-face mirrors ====
Two or more mirrors aligned exactly parallel and facing each other can give an infinite regress of reflections, called an [[infinity mirror]] effect. Some devices use this to generate multiple reflections:
* [[Fabry–Pérot interferometer]]
* [[Laser]] (which contains an [[optical cavity]])
* 3D [[kaleidoscope]] to concentrate light<ref name=more2010/>
* momentum-enhanced [[solar sail]]<ref name=meyer1987/>

==== Military applications ====
Tradition states 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. On the TV show ''[[MythBusters]]'', a team from [[MIT]] tried to recreate the famous "Archimedes Death Ray". They were unsuccessful at starting a fire on a ship.<ref name=myth2019/> Previous attempts to set a 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; such a scenario could have impeded attackers and have provided the origin of the legend. (See [[solar power tower]] for a practical use of this technique.)

Periscopes were used to great effect in war, especially during the World Wars where they were used to peer over the parapet of trenches to ensure that the soldier using the periscope could see safely without the risk of incoming direct fire from other small arms.

==== Seasonal lighting ====
[[File:Kibble Palace Mirror.JPG|left|thumb|A multi-facet mirror in the [[Kibble Palace]] conservatory, [[Glasgow]], Scotland]]

<!-- If this technique becomes popular, don't let this section grow into a vast list of examples. -->
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&nbsp;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 name=bbcn2007/><ref name=apsw207/> In 2013, mirrors were installed to reflect sunlight into the town square in the Norwegian town of [[Rjukan]].<ref name=bbcn2013/> Mirrors can be used to produce enhanced lighting effects in greenhouses or conservatories.

=== Architecture ===
[[File:Mirrored building in Manhattan, 2008.tif|thumb|Mirrored building in Manhattan - 2008]]
[[File:Trump International Hotel and Tower, Chicago, Illinois, Estados Unidos, 2012-10-20, DD 05.jpg|thumb|[[Trump International Hotel and Tower (Chicago)|401 N. Wabash Ave.]] reflects the skyline along the [[Chicago River]] in downtown Chicago]]
{{See also|Architectural glass}}
Mirrors are a popular design-theme in architecture, particularly with [[Modern architecture|late modern]] and [[Post-modern architecture|post-modernist]] high-rise buildings in major cities. Early examples include the Campbell Center in [[Dallas]], which opened in 1972,<ref name=brown2012/> and the [[John Hancock Tower]] (completed in 1976) in Boston.

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 name=vdara2010/> aka the "[[fryscraper]]." In 2013, sunlight reflecting off 20 Fenchurch Street melted parts of a [[Jaguar Cars|Jaguar car]] parked nearby and scorching or igniting the carpet of a nearby barber-shop.<ref name=fench2013/> This building had been nicknamed the "walkie-talkie" because its shape was supposedly similar to a certain model of two-way radio; but after its tendency to overheat surrounding objects became known, the nickname changed to the "walkie-scorchie".

=== Fine art ===

==== Paintings ====
[[File:Titian - Venus with a Mirror - Google Art Project.jpg|thumb|upright|[[Titian]]'s ''[[Venus with a Mirror]]'']]
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 a 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. In the psychology of perception, this is known as the [[Venus effect]].

The mirror is the central device in some of the greatest of European paintings:
* [[Édouard Manet]]'s ''[[A Bar at the Folies-Bergère]]'' (1882)
* [[Titian]]'s ''[[Venus effect|Venus with a Mirror]]''
* [[Jan van Eyck]]'s ''[[Arnolfini Portrait]]''
* [[Pablo Picasso]]'s ''[[Girl before a Mirror]]'' (1932)
* [[Diego Velázquez]]'s ''[[Rokeby Venus]]''
* [[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
* [[Paolo Veronese|Veronese]]'s ''Venus with a Mirror''

Artists have used mirrors to create works and to hone their craft:
* [[Filippo Brunelleschi]] discovered linear perspective with the help of the mirror.<ref name=camp2014/>
* [[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."<ref name=mccur1938/>
* Many [[self-portraits]] are made possible through the use of mirrors, such as great self-portraits by [[Dürer]], [[Frida Kahlo]], [[Rembrandt]], and [[Van Gogh]]. [[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]]'' (1935; also known as ''Self-Portrait in Spherical Mirror'').

Mirrors are sometimes necessary to fully appreciate art work:
* [[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.<ref name=orosz2015/>

==== Sculpture ====
[[File:Arnaldo Dell'Ira (1903-1943) Sala d'aspetto per la casa di M.me B.,1939.jpg|thumb|Mirrors in interior design:
"Waiting room in the house of M.me B.", [[Art Deco]] project by Italian architect [[Arnaldo dell'Ira]], Rome, 1939.]]
* [[Anamorphosis]] projecting sculpture into mirrors
Contemporary anamorphic artist [[Jonty Hurwitz]] uses [[cylindrical]] mirrors to project distorted sculptures.<ref name=hurw2013/>
* Sculptures comprised entirely or in part of mirrors include:
** ''[[:File:Infinity wulsin.jpg|Infinity Also Hurts]]'', a mirror, glass and [[silicone]] sculpture by artist [[Seth Wulsin]]
** ''[[Sky Mirror]]'', a [[public art|public sculpture]] by artist [[Anish Kapoor]]

==== Other artistic mediums ====
[[File:130 - Grove Of Mirrors, Hilary Arnold Baker (4655892606).jpg|thumb|''Grove Of Mirrors'' by [[Hilary Arnold Baker]], [[Romsey]]]]

Some other contemporary artists use mirrors as the [[List of artistic mediums|material of art]]:
* A [[Chinese magic mirror]] is a device 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/>
* [[Specular holography]] uses a large number of curved mirrors embedded in a surface to produce three-dimensional imagery.
* Paintings on mirror surfaces (such as silkscreen printed glass mirrors)
* Special mirror installations:
** ''Follow Me'', a mirror labyrinth by artist [[Jeppe Hein]] (see also, Entertainment: Mirror mazes, below)
** ''Mirror Neon Cube'' by artist Jeppe Hein

==== Religious function of the real and depicted mirror ====
[[File:Melong Dorje.jpg|thumb|Drubthob Melong Dorje (1243–1303), a lineage holder of the [[Vima Nyingtik]], depicted wearing a mirror hanging from his neck]]
In the [[Middle Ages]], mirrors existed in various shapes for multiple uses. Mostly they were used as an accessory for personal hygiene but also as tokens of courtly love, made from [[Ivory carving|ivory]] in the ivory-carving centers in Paris, Cologne and the Southern Netherlands.<ref name=court2018/> They also had their uses in religious contexts as they were integrated in a special form of [[Pilgrim badge|pilgrim badges]] or pewter/lead mirror boxes<ref name=bojm2018/> From the late 14th century. Burgundian ducal inventories show us that the dukes owned a mass of mirrors or objects with mirrors, not only with religious iconography or inscriptions, but combined with reliquaries, religious paintings or other objects that were distinctively used for personal piety.<ref name=sche2013/> Considering mirrors in paintings and book illumination as depicted artifacts and trying to draw conclusions about their functions from their setting, one of these functions is to be an aid in personal prayer to achieve self-knowledge and knowledge of God, in accord with contemporary theological sources. For example, the famous [[Arnolfini Portrait|Arnolfini Wedding]] by [[Jan van Eyck]] shows a constellation of objects that can be recognized as one which would allow a praying man to use them for his personal piety: the mirror surrounded by scenes of the Passion to reflect on it and on oneself, a [[rosary]] as a device in this process, the veiled and cushioned bench to use as a [[prie-dieu]], and the abandoned shoes that point in the direction in which the praying man kneeled.<ref name=sche2013/> The metaphorical meaning of depicted mirrors is complex and many-layered, e.g. as an attribute of [[Mary, mother of Jesus|Mary]], the "speculum sine macula" (mirror without blemish), or as attributes of scholarly and theological wisdom and knowledge as they appear in book illuminations of different [[Four Evangelists|evangelists]] and authors of theological treatises. Depicted mirrors – orientated on the physical properties of a real mirror – can be seen as metaphors of knowledge and reflection and are thus able to remind beholders to reflect and get to know themselves. The mirror may function simultaneously as a symbol and as a device of a moral appeal. That is also the case if it is shown in combination with virtues and vices, a combination which also occurs more frequently in the 15th century: the moralizing layers of mirror metaphors remind the beholder to examine themself thoroughly according to their own virtuous or vicious life. This is all the more true if the mirror is combined with iconography of death. Not only is Death as a corpse or skeleton holding the mirror for the still-living personnel of paintings, illuminations and prints, but the skull appears on the convex surfaces of depicted mirrors, showing the painted and real beholders their future face.<ref name=sche2013/>

=== Decoration ===
[[File:Overmantel.jpg|thumb|upright|[[Fireplace mantel|Chimneypiece]] and overmantel mirror, c. 1750 V&A Museum no. 738:1 to 3–1897]]
[[File:Demo Day 2016 - Design Center (19).jpg|thumb|Glasses with mirrors – Prezi HQ]]
[[File:Dunville's Whisky Pub Mirror 01.jpeg|thumb|A bar mirror bearing the logo of [[Dunville & Co#Dunville's Whisky|Dunville's Whiskey]].]]
Mirrors are frequently used in [[interior decoration]] and as ornaments:
* Mirrors, typically large and unframed, are frequently used in [[interior decoration]] to create an illusion of space and to amplify the apparent size of a room.<ref name=alic2016/> They come also framed in a variety of forms, such as the [[pier glass]] and the overmantel mirror.
* 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 an environment.
* 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. 
* 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''.
* Some pubs and bars hang mirrors depicting the logo of a brand of liquor, beer or drinking establishment.

=== Entertainment ===
* Illuminated rotating [[disco ball]]s covered with small mirrors are used to cast moving spots of light around a dance floor.
* The [[house of mirrors|hall of mirrors]], commonly found in [[amusement park]]s, is an attraction in which a number of [[distorting mirror]]s produce unusual reflections of the visitor.
* Mirrors are employed in [[kaleidoscope]]s, personal entertainment devices invented in [[Scotland]] {{circa |1815}} by Sir [[David Brewster]].
* Mirrors are often used in [[Magic (illusion)|magic]] to create an [[illusion]]. One effect is called [[Pepper's ghost]].
* Mirror [[maze]]s, often found in [[amusement park]]s, 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]] to prevent breakages.<ref name=samu2001/>

=== Film and television ===
Mirrors appear in many movies and TV shows: 
*''[[Black Swan (film)|Black Swan]]'' is a [[psychological horror]] film that frequently incorporates mirrors. Fractured mirrors are prominent in the film, and the character Nina stabs herself with a broken piece of mirror. 
* [[Candyman (1992 film)|''Candyman'']] is a horror film about a [[malevolent spirit]] summoned by speaking its name in front of a mirror.
* ''[[Conan the Destroyer]]'' features a mirror-embedded chamber deep within Thoth-Amon's castle. The mirrors are first used in an illusory fashion to deceive [[Conan the Barbarian|Conan]] once he is separated by his companions, and during a battle sequence it is discovered that by breaking the mirrors he is able to damage and eventually defeat the otherwise-invulnerable wizard Thoth-Amon.
*''[[Dead of Night]]'' is an [[anthology film|anthology]] horror film with one segment titled "The Haunted Mirror," in which a mirror casts a murderous spell. 
*''[[Doctor Strange (2016 film)|Doctor Strange]]'', ''[[Doctor Strange in the Multiverse of Madness]]'', and ''[[Spider-Man: No Way Home]]'' feature the fictional [[Mirror Dimension|mirror dimension]], a parallel dimension in the [[Marvel Cinematic Universe|Marvel Universe]] that reflects objects like a mirror, but in different directions.
*''[[Enter the Dragon]]'''s iconic and final fight scene occurs in a mirrored room. The mirrors create multiple reflections of the fight movements but are eventually smashed.
*''[[The Floorwalker]]'' and ''[[Duck Soup (1933 film)|Duck Soup]]'' contain a mirror scene in which one person comically pretends to be the mirror reflection of someone else. This mirror scene has been imitated in other comedy films and TV shows.<ref>{{cite web |last1=Bouvé |first1=Andrew |title=The Evolution of the Mirror Routine: A Supercut |url=https://slate.com/culture/2014/03/the-mirror-routine-in-movies-supercut-from-duck-soup-the-marx-brothers-and-charlie-chaplin-to-the-muppets-most-wanted-video.html |website=Slate |date=21 March 2014 |access-date=August 24, 2022 |archive-date=24 August 2022 |archive-url=https://web.archive.org/web/20220824204011/https://slate.com/culture/2014/03/the-mirror-routine-in-movies-supercut-from-duck-soup-the-marx-brothers-and-charlie-chaplin-to-the-muppets-most-wanted-video.html |url-status=live }}</ref><ref>{{cite web |title=I Love Lucy: Harpo Marx |url=https://www.imdb.com/title/tt0609287/ |website=IMDb |access-date=August 24, 2022 |archive-date=24 August 2022 |archive-url=https://web.archive.org/web/20220824203928/https://www.imdb.com/title/tt0609287/ |url-status=live }}</ref>
*''[[Hamlet (1996 film)|Hamlet]]'' has a throne room with mirrored walls. Hamlet, played by [[Kenneth Branagh]], gives his famous speech with the words "to be or not to be," looking into these mirrors.<ref>{{cite web |last1=Ebert |first1=Roger |title=Hamlet |url=https://www.rogerebert.com/reviews/hamlet-1996 |website=Rober Ebert |access-date=August 25, 2022 |archive-date=25 August 2022 |archive-url=https://web.archive.org/web/20220825155847/https://www.rogerebert.com/reviews/hamlet-1996 |url-status=live }}</ref> 
*[[Harry Potter and the Philosopher's Stone (film)|''Harry Potter and the Philosopher's Stone'']] includes the magical [[Magical objects in Harry Potter|Mirror of Erised]]. 
*''[[Inception]]'' contains mirrors created in a dream sequence. Ariadne creates two mirrors facing each other that form an infinite number of reflected mirrors. 
*''[[Lady in the Lake]]'', a 1947 [[film noir]], was shot from the [[Point-of-view shot|point of view]] of the protagonist, who is seen only when a mirror is included in the shot.
*''[[Last Night in Soho]]'' is a psychological horror movie with several mirror scenes. The character Ellie occasionally sees her mother's ghost in mirrors. 
*''[[The Matrix]]'' uses various reflections and mirrors throughout the film. Neo watches a broken mirror mend itself, and different objects create reflections.<ref>{{cite web |last1=Sharma |first1=Dhruv |title=The Matrix: What Neo's Mirror Moment Actually Means |url=https://screenrant.com/matrix-neo-mirror-real-world-meaning/ |website=Screenrant |date=4 June 2022 |access-date=August 25, 2022 |archive-date=25 August 2022 |archive-url=https://web.archive.org/web/20220825183843/https://screenrant.com/matrix-neo-mirror-real-world-meaning/ |url-status=live }}</ref>
* ''[[Mirror (1975 film)|Mirror]]'' is a drama film by [[Andrei Tarkovsky]] that includes several scenes with mirrors and several scenes shot in reflection. 
*''[[Mirror Mirror (film)|Mirror Mirror]]'' is a fantasy comedy film based on [[Snow White]] that features a Mirror House and Mirror Queen. 
* [[Mirrors (2008 film)|''Mirrors'']] is a horror film about haunted mirrors that reflect different scenes than those in front of them.
*''[[Persona (1966 film)|Persona]]'' relies on mirror sequences to show how the two women, Bibi and Liv, reflect each other and become more alike.<ref>{{cite web |last1=Kennelly |first1=Kate |title=A Mindscape of Mirrors: Persona and the Cinema of Self-Perception |url=https://brightlightsfilm.com/a-mindscape-of-mirrors-persona-and-the-cinema-of-self-perception/#.Ywe1ni-caF0 |website=Bright Lights Film Journal |date=23 March 2016 |access-date=August 25, 2022}}</ref>
* ''[[Poltergeist III]]'' features mirrors that do not reflect reality and which can be used as portals to an afterlife.
*''[[Psycho (1960 film)|Psycho]]'' by [[Alfred Hitchcock|Alfred Hitchock]] has several shots with mirrors that reflect characters. 
* [[Oculus (film)|''Oculus'']] is a horror film about a haunted mirror that causes people to hallucinate and commit acts of violence.
*''[[Orpheus (film)|Orpheus]]'' includes an important theme of mirrors in connection to aging and death.<ref>{{cite web |last1=Cocteau |first1=Jean |title=Orpheus |url=https://www.criterion.com/current/posts/13-orpheus |website=The Criterion Collection |access-date=August 24, 2022 |archive-date=24 August 2022 |archive-url=https://web.archive.org/web/20220824224308/https://www.criterion.com/current/posts/13-orpheus |url-status=live }}</ref> 
*''[[Sailor Moon]]'' in the fourth story arc has a major theme pertaining to mirrors, which entrap several of the Sailor Senshi, the fiancée of the protagonist, and the villain in the arc.
*''[[Taxi Driver]]'' has a notable scene with a mirror in which the character Travis, played by [[Robert De Niro]], asks himself the famous line, "You talkin' to me?"
*''[[The Lady from Shanghai]]'' has a climatic hall of mirrors scene that has become a [[Trope (cinema)|trope]] in cinema narratives.<ref>{{cite web |title=Through a Glass, Darkly: 'The Lady From Shanghai' and the Legend of Orson Welles |url=https://grantland.com/hollywood-prospectus/through-a-glass-darkly-the-lady-from-shanghai-and-the-legend-of-orson-welles/ |website=Grantland |access-date=August 24, 2022 |archive-date=1 July 2019 |archive-url=https://web.archive.org/web/20190701192511/https://grantland.com/hollywood-prospectus/through-a-glass-darkly-the-lady-from-shanghai-and-the-legend-of-orson-welles/ |url-status=live }}</ref><ref>{{cite web |title=Hall of Mirrors in Movies |url=https://www.imdb.com/list/ls027290183/ |website=IMDb |access-date=August 25, 2022 |archive-date=25 August 2022 |archive-url=https://web.archive.org/web/20220825194044/https://www.imdb.com/list/ls027290183/ |url-status=live }}</ref>
*''[[Raging Bull]]'' ends with the character Jake talking to himself in a mirror, a scene that was reused in ''[[Boogie Nights]]''. 
*''[[The Shining (film)|The Shining]]'' is a horror movie that includes several scenes with mirrors. Every time the character Jack encounters a ghost, a mirror is present.
* ''[[The 10th Kingdom]]'' [[miniseries]] requires the characters to use a magic mirror to travel between New York City (the 10th Kingdom) and the Nine Kingdoms of [[fairy tale]].
*''[[The Twilight Zone (1959 TV series)|The Twilight Zone]]'' episode "[[The Mirror (The Twilight Zone)|The Mirror]]" features a mirror that the character Clemente believes can provide visions and information about enemies.
*''[[Us (2019 film)|Us]]'' is a horror film that includes a girl seeing a [[doppelgänger]] of herself in a [[house of mirrors]] in a [[funhouse]]. The mirror images reflect the similarities in the clones throughout the film.
*''[[Vertigo (film)|Vertigo]]'' includes several appearances of mirrors with both Scottie and Madeleine in the frame.<ref>{{cite web |title=Mirrors in Hitchcock Movies |url=https://www.alfred-hitchcock-films.net/theme-mirrors.htm |website=Alfred Hitchcock Films |access-date=August 25, 2022 |archive-date=25 August 2022 |archive-url=https://web.archive.org/web/20220825162331/https://www.alfred-hitchcock-films.net/theme-mirrors.htm }}</ref>

=== Literature ===
{{see also|Category:Fiction about mirrors|l1=Fiction about mirrors}}
[[File:Snow White Mirror 4.png|thumb|upright|An illustration from page 30 of ''[[:is:Mjallhvít|Mjallhvít]]'' ([[Snow White]]) an 1852 Icelandic translation of the [[Brothers Grimm|Grimm]]-version fairytale]]
[[File:Taijitu and demon warding mirror.jpg|thumb|upright|[[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 a dwelling from bad luck]]
Mirrors featured in literature:
* [[Christian biblical canons|Christian Bible]] passages, 1 Corinthians 13:12 ("[[Through a glass, darkly (phrase)|Through a Glass Darkly]]") and 2 Corinthians 3:18, reference a dim mirror-image or poor mirror-reflection.
* [[Narcissus (mythology)|Narcissus]] of [[Greek mythology]] wastes away while gazing, self-admiringly, at his reflection in water.
* Elsewhere in Greek Mythology, [[Perseus]] is said to have defeated the [[Gorgon]] [[Medusa]] with the aid of a mirrored shield which allowed him to avoid the petrifying effect of her visage by only viewing her reflection.
* The Song dynasty history ''[[Zizhi Tongjian]]'' ''Comprehensive Mirror in Aid of Governance'' by Sima Guang is so titled because "mirror" (鑑, jiàn) is used metaphorically in Chinese to refer to gaining insight by reflecting on past experience or history. 
* In the late 6th century Chinese folktale ''[[The Broken Mirror Restored]]'' two lovers who are separated by war break a mirror in two so that they might find each other again by identifying the other half of the mirror. The phrase "broken mirror restored", or "broken mirror joined together" has been used as an idiom to suggests the happy reunion of a separated couple.<ref>{{Cite web |date=2011-02-18 |title=Chinese history and culture reflected by bronze mirrors |url=http://www.chinadaily.com.cn/life/2011-02/18/content_12041009.htm |access-date=2024-01-17 |website=China Daily |archive-date=17 January 2024 |archive-url=https://web.archive.org/web/20240117141537/http://www.chinadaily.com.cn/life/2011-02/18/content_12041009.htm |url-status=live }}</ref> 
* In the European [[fairy tale]], ''[[Snow White]]'' (collected by the 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 the [[Aarne-Thompson-Uther Index]] tale type ATU 329, "Hiding from the Devil (Princess)", the protagonist must find a way to hide from a princess, who, in many variants, owns a magical mirror that can see the whole world.
* In [[Alfred, Lord Tennyson|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.
* [[Hans Christian Andersen]]'s fairy tale ''[[The Snow Queen]]'', features the devil, in a form of an evil troll,<ref name=ande1983/> who made a magic mirror that distorts the appearance of everything that it reflects.
* [[Lewis Carroll]]'s ''[[Through the Looking-Glass]] and What Alice Found There'' (1871) has become one of the best-loved exemplars of the use of mirrors in literature. The text itself utilizes a narrative that mirrors that of its predecessor, ''[[Alice's Adventures in Wonderland]]''.<ref name=carr1872/>
* 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 name=call2009/><ref name=wild2010/>
* [[W. H. Auden]]'s villanelle "Miranda" repeats the refrain: "My dear one is mine as mirrors are lonely".
* The short story ''[[Tlön, Uqbar, Orbis Tertius]]'' (1940) by [[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.
* ''The Trap'', a short story by [[H.P. Lovecraft]] and Henry S. Whitehead, centers around a mirror. "It was on a certain Thursday morning in December that the whole thing began with that unaccountable motion I thought I saw in my antique Copenhagen mirror. Something, it seemed to me, stirred—something reflected in the glass, though I was alone in my quarters."<ref name=love/>
* [[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 & Dragons 3rd edition|Manual of the Planes]]'' (2000), is The Plane of Mirrors (page 204).<ref name=dung2001/> 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.
* ''The Mirror Thief'', a novel by Martin Seay (2016),<ref name=seay2016/> includes a fictional account of industrial espionage surrounding mirror-manufacturing in 16th-century Venice.
* ''[[The Glass Floor]]'', a short story by [[Stephen King]], concerns a mysterious and deadly mirrored floor.
* ''[[The Reaper's Image]]'', a short story by [[Stephen King]], concerns a rare Elizabethan mirror that displays the Reaper's image when viewed, which symbolises the death of the viewer.
* Kilgore Trout, a protagonist of [[Kurt Vonnegut]]'s novel ''[[Breakfast of Champions]]'', believes that mirrors are windows to other universes, and refers to them as "leaks", a recurring motif in the book.
*In ''[[The Fellowship of the Ring]]'' by [[J. R. R. Tolkien]], the [[Mirror of Galadriel]] allows one to see things of the past, present and possible future. The mirror additionally appears in the [[The Lord of the Rings: The Fellowship of the Ring|movie adaptation]].<ref>{{cite web |last1=Hedash |first1=Kara |title=Lord Of The Rings: What Frodo Saw In The Mirror of Galadriel |url=https://screenrant.com/lord-rings-frodo-vision-galadriel-mirror-explained/ |website=Screenrant |date=10 July 2019 |access-date=August 25, 2022 |archive-date=25 August 2022 |archive-url=https://web.archive.org/web/20220825163841/https://screenrant.com/lord-rings-frodo-vision-galadriel-mirror-explained/ |url-status=live }}</ref>

== <span id="Mirrors and animals"></span> Mirror test ==
{{Main|Mirror test}}

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]]:
* [[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 name=palm2014/><ref name=coren/><ref name=archer/>
* All [[great ape]]s:
** [[Bonobo]]s<ref name=miller/>
** [[Chimpanzee]]s<ref name=miller/><ref name=poin2003/>
** [[Orangutan]]s<ref name=natgeo/>
** [[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 name=patt2012/>) passing the test.
* [[Bottlenose dolphins]]<ref name=mart1995/>
* [[Orcas]]<ref name=delf2001/>
* [[Elephants]]<ref name=plot2006/>
* [[European magpie]]s<ref name=prio2008/>

== See also ==
{{div col|colwidth=28em}}
* [[Anish Kapoor]] (artist working with mirrors)
* [[Aranmula kannadi]]
* [[Chirality (mathematics)]]
* [[Corner reflector]]
* [[Curved mirror]]
* [[Deformable mirror]]
* [[Digital micromirror device]]
* [[Heliotrope (instrument)]]
* [[Honeycomb mirror]]
* [[List of telescope parts and construction]]
* ''[[Melong]]''
* [[Mirror armour]]
* [[Non-reversing mirror]]
* [[Mirror writing]]
* [[Mirrors in Mesoamerican culture]]
* [[Perfect mirror]]
* [[Periscope]]
* [[Selfie]]
* [[Spectrophobia]]
* [[TLV mirror]]
* [[Venus effect]]
* {{annotated link|Toli (shamanism)|Toli}}
{{div col end}}

== References ==
{{reflist|refs=

<ref name=U1>{{Cite book | author=M. A. Kallistratova | title=Acoustic Remote Sensing Applications | chapter=Physical grounds for acoustic remote sensing of the atmospheric boundary layer | volume=69 | pages=3–34 | year=1997 | doi=10.1007/BFb0009558 | series=Lecture Notes in Earth Sciences | isbn=978-3-540-61612-2 | bibcode=1997LNES...69....3K | publisher=Springer }}</ref>

<ref name=alic2016>{{cite web |url=http://alice.ia.net/portfolio/mad-hatter/ |title=Product Design: Futuristic, Liquid Mirror Door |access-date=13 October 2016 |archive-url=https://web.archive.org/web/20161014062416/http://alice.ia.net/portfolio/mad-hatter/ |archive-date=14 October 2016 }}</ref>

<ref name=ande1983>{{cite book|last=Andersen|first=Hans Christian|others=trans. Erik Christian Haugaard|year=1983|title=The Complete Fairy Tales and Stories|chapter=The Snow Queen|chapter-url=https://books.google.com/books?id=pKO5Bydk2QEC|location=United States|publisher=Anchor Books|isbn=978-0-307-77789-8|access-date=3 December 2013 }}</ref>

<ref name=ande2000>{{Cite book|url=https://books.google.com/books?id=IEhJpyEBKYIC&pg=PA263|title=The Dental Assistant|last1=Anderson|first1=Pauline Carter|last2=Pendleton|first2=Alice E.|date=2000|publisher=Cengage Learning|isbn=978-0-7668-1113-3|language=en}}</ref>

<ref name=ande2008>[http://www.c-s-p.org/Flyers/9781847181930-sample.pdf The Book of the Mirror] {{webarchive|url=https://web.archive.org/web/20080411060903/http://www.c-s-p.org/Flyers/9781847181930-sample.pdf |date=11 April 2008 }}, Cambridge Scholars Publishing, edited by Miranda Anderson</ref>

<ref name=apsw207>{{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 |archive-url=https://web.archive.org/web/20090317092530/http://www.cbsnews.com/stories/2007/02/12/ap/world/mainD8N8AED80.shtml |archive-date=17 March 2009 }}</ref>

<ref name=archer>{{cite book |last=Archer |first=John |year=1992 |title=Ethology and Human Development |publisher=Rowman & Littlefield |isbn=978-0-389-20996-6}}</ref>

<ref name=azop2016>{{Cite web|url=https://wp.optics.arizona.edu/optomech/wp-content/uploads/sites/53/2016/08/10-Specifying-optical-components.pdf|title=Tolerancing Optical Systems|access-date=7 October 2023|website=wp.optics.arizona.edu|archive-date=14 February 2024|archive-url=https://web.archive.org/web/20240214165533/https://wp.optics.arizona.edu/optomech/wp-content/uploads/sites/53/2016/08/10-Specifying-optical-components.pdf|url-status=live}}</ref>

<ref name=bbcn2007>{{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 | access-date=12 May 2010 | archive-date=15 December 2010 | archive-url=https://web.archive.org/web/20101215073938/http://news.bbc.co.uk/2/hi/europe/6189371.stm | url-status=live }}</ref>

<ref name=bbcn2013>[https://www.bbc.co.uk/news/world-europe-24747720 ''Mirrors finally bring winter sun to Rjukan in Norway''] {{Webarchive|url=https://web.archive.org/web/20170801213038/http://www.bbc.co.uk/news/world-europe-24747720 |date=1 August 2017 }}, BBC News, 30 October 2013</ref>

<ref name=boba2014>{{cite web |url=http://www.bobatkins.com/photography/tutorials/mirror.html |title=Mirror Lenses – how good? Tamron 500/8 SP vs Canon 500/4.5L |publisher=Bobatkins.com |access-date=3 June 2014 |archive-date=25 May 2014 |archive-url=https://web.archive.org/web/20140525040844/http://www.bobatkins.com/photography/tutorials/mirror.html |url-status=live }}</ref>

<ref name=bojm2018>{{Cite web|url=http://collectie.boijmans.nl/en/object/127762|title=Lid of a mirror box|website=Museum Bojmans van Beuningen, Rotterdam|access-date=29 July 2018 |archive-date=29 July 2018|archive-url=https://web.archive.org/web/20180729200538/http://collectie.boijmans.nl/en/object/127762}} See this example of a pewter mirror box from around 1450–1500.</ref>

<ref name=bonn2011>Sabine Melchoir-Bonnet (2011): ''[https://books.google.com/books?hl=en&id=P-c1g6QIPHIC The Mirror: A History]'' by  – Routledge 2011. {{isbn|978-0-415-92448-1}}</ref>

<ref name=boyd1997>{{cite journal |title=Brillouin-enhanced four-wave-mixing vector phase-conjugate mirror with beam-combining capability |journal=Optics Letters|volume=22 |issue=6 |pages=360–362  |year=1997 |last1= Bowers |first1=M W |last2= Boyd |first2=R W |last3= Hankla |first3=A K |doi=10.1364/OL.22.000360|pmid=18183201|bibcode=1997OptL...22..360B|s2cid=25530526 }}</ref>

<ref name=brit2009>{{cite web |url= http://www.mirrorresilvering.com/a_brief_history_of_mirrors.htm |title= A Brief History of Mirrors |publisher= Encyclopædia Britannica |access-date= 14 August 2009 |archive-url= https://web.archive.org/web/20200428074332/http://www.mirrorresilvering.com/a_brief_history_of_mirrors.htm |archive-date= 28 April 2020 }}</ref>

<ref name=brown2012>{{cite news|url=http://www.dallasnews.com/business/columnists/steve-brown/20120517-reflections-on-mirrored-glass-70s-bling-buildings-still-shine.ece|title=Reflections on mirrored glass: '70s bling buildings still shine|author=Steve Brown|newspaper=The Dallas Morning News|date=17 May 2012|access-date=10 March 2014|archive-date=10 March 2014|archive-url=https://web.archive.org/web/20140310170617/http://www.dallasnews.com/business/columnists/steve-brown/20120517-reflections-on-mirrored-glass-70s-bling-buildings-still-shine.ece|url-status=live}}</ref>

<ref name=call2009>{{Cite news|url=https://www.theguardian.com/culture/2009/sep/19/oscar-wilde-picture-dorian-gray|title=Mirror, mirror|publisher=The Guardian: Culture Web|newspaper=The Guardian |author=Simon Callow|date=19 September 2009 |access-date=20 November 2010}}</ref>

<ref name=camboldf>Entry "[https://dictionary.cambridge.org/us/dictionary/english/looking-glass looking glass]" in the online ''Cambridge Dictionary''. Accessed on 4 May 2020.</ref>

<ref name=camp2014>{{Cite book|url=https://books.google.com/books?id=EfpMBQAAQBAJ&pg=PA40|title=The First Frame|last=Camp|first=Pannill|date=4 December 2014|publisher=Cambridge University Press|isbn=978-1-107-07916-8|language=en}}</ref>

<ref name=carr1872>{{cite book |last1=Carroll |first1=Lewis |title=Through the Looking-glass: And what Alice Found There |url=https://books.google.com/books?id=aOKruPEWBqEC |publisher=Macmillan Children's |access-date=24 February 2019|year=1872 |isbn=978-0-333-37008-7 }}</ref>

<ref name=charm2016>{{cite web| url=https://www.reflectingdesign.com/design_classics_convex-mirrors/| title=The Charm of Convex Mirrors| work=Reflecting Design &#124; Decorative Convex and Flat Mirrors| date=6 February 2016| access-date=29 January 2018| archive-date=16 January 2019| archive-url=https://web.archive.org/web/20190116020948/https://www.reflectingdesign.com/design_classics_convex-mirrors/}}</ref>

<ref name=cheng2009>''The Principles of Astronomical Telescope Design'' By Jingquan Cheng -- Springer 2009 Page 87</ref>

<ref name=coren>{{cite book |title=How dogs think |author=Stanley Coren |isbn=978-0-7432-2232-7 |year=2004 |publisher=Free Press |url=https://archive.org/details/howdogsthinkunde00core }}</ref>

<ref name=court2018>{{Cite web|url=http://www.gothicivories.courtauld.ac.uk/|title=Gothic Ivories Project at The Courtauld Institute of Art, London|date=1 October 2008|website=www.gothicivories.courtauld.ac.uk|access-date=29 July 2018 |archive-url=https://web.archive.org/web/20180728213440/http://www.gothicivories.courtauld.ac.uk/|archive-date=28 July 2018}} Search for "mirror case" or "mirror".</ref>

<ref name=degy>[http://www.digitalegypt.ucl.ac.uk/metal/mirrors.html Mirrors in Egypt] {{Webarchive|url=https://web.archive.org/web/20141101133637/http://www.digitalegypt.ucl.ac.uk/metal/mirrors.html |date=1 November 2014 }}, Digital Egypt for Universities</ref>

<ref name=delf2001>{{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 |doi=10.1016/s0376-6357(01)00134-6|s2cid= 31124804 }}</ref>

<ref name=dung2001>{{cite book| title=Manual of the Planes| isbn=978-0-7869-1850-8| year=2001| first=Jeff| last= Grubb |author2=David Noonan |author3=Bruce R. Cordell| publisher=Wizards of the Coast| url=http://www.wizards.com/default.asp?x=products/dndacc/882420000| archive-url=https://web.archive.org/web/20030704155902/http://wizards.com/default.asp?x=products/dndacc/882420000| archive-date=4 July 2003}}</ref>

<ref name=duzg2011>{{cite book |title=Remote Sensing of the Mine Environment |first1=H. Şebnem |last1=Düzgün |first2=Nuray |last2=Demirel |publisher=CRC Press |year=2011 |page=24}}</ref>

<ref name=enoch>{{cite journal |title= History of Mirrors Dating Back 8000 Years |date=October 2006|last1=Enoch |first1=Jay|volume=83 |issue=10 |pages=775–781 |journal=Optometry and Vision Science |doi=10.1097/01.opx.0000237925.65901.c0 |pmid=17041324|s2cid=40335224}}</ref>

<ref name=eso2013>{{cite news|title=Super-thin Mirror Under Test at ESO|url=http://www.eso.org/public/images/potw1307a/|access-date=19 February 2013|newspaper=ESO Picture of the Week|archive-date=15 March 2013|archive-url=https://web.archive.org/web/20130315152407/http://www.eso.org/public/images/potw1307a/|url-status=live}}</ref>

<ref name=fench2013>{{cite news|url = https://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|newspaper = NPR|date = 3 September 2013|last1 = Memmott|first1 = Mark|access-date = 4 April 2018|archive-date = 30 April 2015|archive-url = https://web.archive.org/web/20150430102909/http://www.npr.org/blogs/thetwo-way/2013/09/03/218536265/death-ray-ii-london-building-reportedly-roasts-cars|url-status = live}}</ref>

<ref name=fior2009>{{cite web |url= http://www.lantiquaire.us/origins-of-mirrors.html |title= The Origins of Mirrors and their uses in the Ancient World |first= Helen |last= Fioratti |publisher= L'Antiquaire & the Connoisseur |access-date= 14 August 2009 |archive-url= https://web.archive.org/web/20110203052336/http://www.lantiquaire.us/origins-of-mirrors.html |archive-date= 3 February 2011 }}</ref>

<ref name=fried2001>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>

<ref name=greav1989>''Synchrotron Radiation Sources and Applications'' By G.N Greaves, I.H Munro -- Sussp Publishing 1989</ref>

<ref name=hads1993>{{Cite journal |jstor = 1506387|title = The Tin-Mercury Mirror: Its Manufacturing Technique and Deterioration Processes|journal = Studies in Conservation|volume = 38|issue = 1|pages = 3–16|last1 = Hadsund|first1 = Per|year = 1993|doi=10.1179/sic.1993.38.1.3}}</ref>

<ref name=holl2009>{{cite web |url= http://www.isnare.com/?aid=387476&ca=Advice |title= Mirrors |first= Patricia |last= Holland |publisher= Isnare Free Articles |access-date= 14 August 2009 |archive-date= 3 March 2016 |archive-url= https://web.archive.org/web/20160303195655/http://www.isnare.com/?aid=387476&ca=Advice |url-status= live }}</ref>

<ref name=hopk1910>{{cite book|author=Albert Allis Hopkins|title=The Scientific American cyclopedia of formulas: partly based upon the 28th ed. of Scientific American cyclopedia of receipts, notes and queries|url=https://archive.org/details/b31361523|year=1910|publisher=Munn & co., inc.|page=[https://archive.org/details/b31361523/page/89 89]}}</ref>

<ref name=hurw2013>{{cite web |url=http://www.thisiscolossal.com/2013/01/the-skewed-anamorphic-sculptures-and-engineered-illusions-of-jonty-hurwitz/ |title=The skewed anamorphic sculptures and engineered illusions of Jonty Hurwitz |publisher=Christopher Jobson, Colossal |date=21 January 2013 |access-date=12 February 2015 |archive-date=12 February 2015 |archive-url=https://web.archive.org/web/20150212185522/http://www.thisiscolossal.com/2013/01/the-skewed-anamorphic-sculptures-and-engineered-illusions-of-jonty-hurwitz/ |url-status=live }}</ref>

<ref name=iriw2018>{{Cite web|url=https://iidesignworld.com/2018/08/02/mirror-reflection-interesting-materialsitems-to-use-in-interior-design-i/|title=Mirror Reflection – Interesting Materials to use in interior design (I) – Iri's Interior Design World|language=en-US|access-date=19 February 2019|archive-date=20 February 2019|archive-url=https://web.archive.org/web/20190220063000/https://iidesignworld.com/2018/08/02/mirror-reflection-interesting-materialsitems-to-use-in-interior-design-i/|url-status=live}}</ref>

<ref name=kali>{{Cite book|url=https://books.google.com/books?id=5ha9BgAAQBAJ&pg=PA6|title=The Gist of NCERT -- GENERAL SCIENCE |author=Editorial Board|publisher=Kalinjar Publications|isbn=978-93-5172-018-8|language=en}}</ref>

<ref name=katz2016>{{Cite book|url=https://books.google.com/books?id=5y9_CgAAQBAJ&pg=PA1211|title=Physics for Scientists and Engineers: Foundations and Connections|last=Katz|first=Debora M.|date=1 January 2016|publisher=Cengage Learning|isbn=978-1-337-02636-9|language=en}}</ref>

<ref name=kels2007>[http://www.umich.edu/~kelseydb/Exhibits/WondrousGlass/RomanGlass-Wondrous.html Wondrous Glass: Images and Allegories] {{Webarchive|url=https://web.archive.org/web/20071213064637/http://www.umich.edu/~kelseydb/Exhibits/WondrousGlass/RomanGlass-Wondrous.html |date=13 December 2007 }}, Kelsey Museum of Archaeology</ref>

<ref name=king2000>{{Cite book|url=https://archive.org/details/kingfisherscienc00tayl|url-access=registration|page=[https://archive.org/details/kingfisherscienc00tayl/page/266 266]|title=The Kingfisher Science Encyclopedia|last=Taylor|first=Charles|date=2000|publisher=Kingfisher|isbn=978-0-7534-5269-1|language=en}}</ref>

<ref name=klei1989>''Mirrors and windows for high power/high energy laser systems'' by Claude A Klein -- SPIE Optical Engineering Press 1989 Page 158</ref>

<ref name=lanz2012>{{Cite book|url=https://books.google.com/books?id=71dgCaECxcQC&pg=PA40|title=Quantum Radar|last=Lanzagorta|first=Marco|date=2012|publisher=Morgan & Claypool Publishers|isbn=978-1-60845-826-4|language=en}}</ref>

<ref name=lard1845>{{Cite book|url=https://books.google.com/books?id=q-MMAAAAYAAJ&pg=PA5|title=Popular Lectures on Astronomy: Delivered at the Royal Observatory of Paris|last1=Arago|first1=François|last2=Lardner|first2=Dionysius|date=1845|publisher=Greeley & McElrath|language=en}}</ref>

<ref name=leon2006>''Mems/Nems: Volume 1 Handbook Techniques and Applications Design Methods'' By Cornelius T. Leondes -- Springer 2006 Page 203</ref>

<ref name=lewis2008>''X-Ray Lasers 2008: Proceedings of the 11th International Conference'' By Ciaran Lewis, Dave Riley == Springer 2009 Page 34</ref>

<ref name=lieb185>{{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 | url = https://zenodo.org/record/1427076 | access-date = 29 August 2020 | archive-date = 18 June 2021 | archive-url = https://web.archive.org/web/20210618210416/https://zenodo.org/record/1427076 | url-status = live }}</ref>

<ref name=love>{{cite web|url=http://www.hplovecraft.com/writings/texts/fiction/trap.aspx|title="The Trap" by H. P. Lovecraft|work=hplovecraft.com}}</ref>

<ref name=mark1996>{{cite journal | last1 = Smith | first1 = A. Mark | year = 1996 | title = Ptolemy's Theory of Visual Perception: An English Translation of the "Optics" with Introduction and Commentary | journal = Transactions of the American Philosophical Society |series=New Series | volume = 86 | issue = 2| pages = iii–300 | doi=10.2307/3231951| jstor = 3231951 }}</ref>

<ref name=mart1995>{{cite book |title=Self-awareness in Animals and Humans: Developmental Perspectives |author1=Marten, K. |author2=Psarakos, S. |name-list-style=amp |chapter=Evidence of self-awareness in the bottlenose dolphin (''Tursiops truncatus'') |editor=Parker, S.T. |editor2=Mitchell, R. |editor3=Boccia, M. |pages=361–379 |year=1995 |publisher=Cambridge University Press |chapter-url=http://earthtrust.org/delbook.html |access-date=4 October 2008 |archive-url=https://web.archive.org/web/20081013081149/http://earthtrust.org/delbook.html |archive-date=13 October 2008}}</ref>

<ref name=matt2004>''The Foundations of Vacuum Coating Technology'' By D. M. Mattox -- Springer 2004 Page 37</ref>

<ref name=mccur1938>Leonardo da Vinci, ''The Notebooks of Leonardo Da Vinci'', XXIX : Precepts of the Painter, Tr. Edward MacCurdy (1938)</ref>

<ref name=meyer1987>{{citation|title=The laser elevator – Momentum transfer using an optical resonator|last1=Meyer|first1=Thomas R.|last2=Mckay|first2=Christopher P.|last3=Mckenna|first3=Paul M.|date=1 October 1987|publisher=[[NASA]]|id=IAF PAPER 87–299|url=https://ntrs.nasa.gov/search.jsp?R=19880028776|access-date=7 July 2017|archive-date=5 March 2016|archive-url=https://web.archive.org/web/20160305013610/http://ntrs.nasa.gov/search.jsp?R=19880028776|url-status=live}}</ref>

<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 |access-date=21 May 2009 |archive-date=5 June 2009 |archive-url=https://web.archive.org/web/20090605163645/http://www.americanchronicle.com/articles/view/102661 |url-status=live }}</ref>

<ref name=mlink2014>{{cite web|url=http://www.mirrorlink.org/tech/manufacture.htm |title=Mirror Manufacturing and Composition |publisher=Mirrorlink.org |access-date=3 June 2014 |url-status=usurped |archive-url=https://web.archive.org/web/20150214231103/http://mirrorlink.org/tech/manufacture.htm |archive-date=14 February 2015}}</ref>

<ref name=more2010>{{cite journal|title=Output irradiance of tapered lightpipes|journal=JOSA A|volume=27|issue=9|pages=1985–93|year=2010|url=http://fisica.uaz.edu.mx/~imoreno/Publicaciones/JOSA2010.pdf|doi=10.1364/JOSAA.27.001985|pmid=20808406|author=Ivan Moreno|bibcode=2010JOSAA..27.1985M|s2cid=5844431 |access-date=3 September 2011|archive-url=https://web.archive.org/web/20120331162520/http://fisica.uaz.edu.mx/~imoreno/Publicaciones/JOSA2010.pdf|archive-date=31 March 2012}}</ref>

<ref name=mung1999>{{cite web |url=http://www.usna.edu/Users/physics/mungan/Scholarship/FaradayIsolators.pdf |title=Faraday Isolators and Kirchhoff's Law: A Puzzle |access-date=18 July 2006 |last=Mungan |first=C.E. |year=1999 |archive-date=16 March 2013 |archive-url=https://web.archive.org/web/20130316070609/http://usna.edu/Users/physics/mungan/Scholarship/FaradayIsolators.pdf }}</ref>

<ref name=myth2019>{{cite web |title=2.009 Archimedes Death Ray: Testing with MythBusters |url=http://web.mit.edu/2.009/www//experiments/deathray/10_Mythbusters.html |website=Massachusetts Institute of Technology |access-date=9 November 2019 |archive-date=28 May 2013 |archive-url=https://web.archive.org/web/20130528134958/http://web.mit.edu/2.009/www/experiments/deathray/10_Mythbusters.html }}</ref>

<ref name=natgeo>{{cite web |url= https://www.youtube.com/watch?v=W-pc_M2qI74 | archive-url=https://web.archive.org/web/20101201051415/http://www.youtube.com//watch?v=W-pc_M2qI74| archive-date=1 December 2010 |title=National Geographic documentary "Human Ape" |website=[[YouTube]] |access-date =11 June 2010}}</ref>

<ref name=need1974>{{cite book|author=Joseph Needham|title=Science and Civilisation in China|url=https://books.google.com/books?id=BYixSmXUCuMC&pg=PA238|year=1974|publisher=Cambridge University Press|isbn=978-0-521-08571-7|page=238}}</ref>

<ref name=okul1980>{{cite journal |title=Laser interferometer with wavefront reversing mirrors |journal=Sov. Phys. JETP|volume=52 |issue=5 |page=847 |year=1980 |last1= Basov |first1=N G |last2= Zubarev |first2=I G |last3= Mironov |first3=A B |last4= Mikhailov |first4= S I |last5= Okulov |first5= A Yu |bibcode=1980ZhETF..79.1678B}}</ref>

<ref name=okul2014>{{cite journal |title=Coherent chirped pulse laser network with Mickelson phase conjugator |journal=Applied Optics|volume=53 |issue=11 |pages=2302–2311 |year=2014|last1= Okulov |first1=A Yu|doi=10.1364/AO.53.002302  |pmid=24787398|arxiv=1311.6703|bibcode=2014ApOpt..53.2302O|s2cid=118343729 }}</ref>

<ref name=orosz2015>{{Cite web|url=https://www.ignant.com/2015/01/30/anamorphic-art-by-istvan-orosz/|title=Anamorphic Art by István Orosz|last=Kurze|first=Caroline|date=30 January 2015|website=Ignant|archive-url=https://web.archive.org/web/20171203153855/https://www.ignant.com/2015/01/30/anamorphic-art-by-istvan-orosz/|archive-date=3 December 2017}}</ref>

<ref name=pale2015>{{Cite book|url=https://books.google.com/books?id=oAC5CgAAQBAJ&pg=PA35|title=Concentrating Solar Power and Desalination Plants: Engineering and Economics of Coupling Multi-Effect Distillation and Solar Plants|last1=Palenzuela|first1=Patricia|last2=Alarcón-Padilla|first2=Diego-César|last3=Zaragoza|first3=Guillermo|date=9 October 2015|publisher=Springer|isbn=978-3-319-20535-9|language=en}}</ref>

<ref name=palm2014>{{cite web |url=http://www.ulm.edu/~palmer/ConsciousnessandtheSymbolicUniverse.htm |title=Consciousness and the Symbolic Universe |publisher=Ulm.edu |access-date=3 June 2014 |archive-date=6 June 2002 |archive-url=https://web.archive.org/web/20020606190142/http://www.ulm.edu/~palmer/ConsciousnessandtheSymbolicUniverse.htm |url-status=live }}</ref>

<ref name=patt2012>Francine Patterson and Wendy Gordon [http://www.animal-rights-library.com/texts-m/patterson01.htm The Case for Personhood of Gorillas] {{Webarchive|url=https://web.archive.org/web/20120725051416/http://www.animal-rights-library.com/texts-m/patterson01.htm |date=25 July 2012 }}. In ''[[The Great Ape Project]]'', ed. Paola Cavalieri and Peter Singer, St. Martin's Griffin, 1993, pp. 58–77.</ref>

<ref name=pend2004>Mark Pendergrast (2004): ''[[Mirror Mirror: A History of the Human Love Affair With Reflection]]''. Basic Books. {{ISBN|0-465-05471-4}}</ref>

<ref name=plin0077>Pliny the Elder (ca. 77 CE): ''[[Natural History (Pliny)|Natural History]]''.</ref>

<ref name=plot2006>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] {{Webarchive|url=https://web.archive.org/web/20080516201740/http://www.pnas.org/cgi/content/abstract/0608062103v1 |date=16 May 2008 }}</ref>

<ref name=poin2003>{{cite journal |author=Monique W de Veer |author2=Gordon G Gallup Jr |author3=Laura A Theall |author4=Ruud van den Bos |author5=Daniel J Povinelli |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|pmid=12459221 |year=2003|s2cid=9400080 }}</ref>

<ref name=prio2008>{{cite journal|first1=Helmut |last1=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 |year=2008 |doi=10.1371/journal.pbio.0060202 |volume=6 |page=e202 |pmid=18715117 |issue=8 |pmc=2517622 |editor1-last=De Waal |editor1-first=Frans |doi-access=free }}</ref>

<ref name=pro00>{{cite journal | title= X-ray parabolic collimator with depth-graded multilayer mirror | author= V.V. Protopopov |author2=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>

<ref name=pulk1999>H. Pulker, H.K. Pulker (1999): ''Coatings on Glass''. Elsevier 1999</ref>

<ref name=rapp2009>Archaeominerology By George Rapp – Springer Verlag Berlin Heidelberg 2009 page 180</ref>

<ref name=rash1990>{{cite journal | last1 = Rashed | first1 = Roshdi | year = 1990 | title = A Pioneer in Anaclastics: Ibn Sahl on Burning Mirrors and Lenses | journal = Isis | volume = 81 | issue = 3| pages = 464–491 [465, 468, 469] | doi = 10.1086/355456 | s2cid = 144361526 }}</ref>

<ref name=rayle1901>{{cite journal |author=Rayleigh |title=On the magnetic rotation of light and the second law of thermodynamics |journal= Nature|volume=64 | page= 577 |date=10 October 1901 |issue=1667|doi=10.1038/064577e0 |doi-access=free }}</ref>

<ref name=roma2019>{{cite web | url=https://penelope.uchicago.edu/Thayer/E/Roman/Texts/secondary/SMIGRA*/Speculum.html | title=Speculum | access-date=31 July 2019 }}{{Dead link|date=April 2020 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

<ref name=samu2001>{{cite book | title=The American Amusement Park | url=https://archive.org/details/americanamusemen00ajps | url-access=registration | publisher=MBI Publishing Company | author=Dale Samuelson, Wendy Yegoiants | year=2001 | pages=[https://archive.org/details/americanamusemen00ajps/page/65 65]| isbn=978-0-7603-0981-0 }}</ref>

<ref name=saun2004>{{Cite book|url=https://books.google.com/books?id=GSKSJdpt4HAC&pg=PT33|title=Aluminum and the Elements of Group 13|last=Saunders|first=Nigel|date=6 February 2004|publisher=Capstone Classroom|isbn=978-1-4034-5495-9|language=en}}</ref>

<ref name=scha2011>''Molded Optics: Design and Manufacture'' By Michael Schaub, Jim Schwiegerling, Eric Fest, R. Hamilton Shepard, Alan Symmons -- CRC Press 2011 Page 88–89</ref>

<ref name=sche2013>{{Cite book|title=Das altniederländische Stifterbild. Emotionsstrategien des Sehens und der Selbsterkenntnis|last=Scheel|first=Johanna|publisher=Gebr. Mann|year=2013|isbn=978-3-7861-2695-9|location=Berlin|pages=342–351}}</ref>

<ref name=schr1969>{{Cite book|url=https://archive.org/details/planningremodeli00schr|url-access=registration|title=Planning & remodeling bathrooms|last=Schram|first=Joseph F.|date=1 January 1969|publisher=Lane Books|isbn=978-0-376-01322-4|language=en}}</ref>

<ref name=seay2016>{{cite book| title=The Mirror Thief| isbn=978-1-61219-514-8| year=2016| first=Martin| last= Seay| publisher=Melville House}}</ref>

<ref name=stoc>[http://www.tekniskamuseet.se/templates/Page.aspx?id=12447 The National Museum of Science and Technology, Stockholm] {{webarchive |url=https://web.archive.org/web/20090703101416/http://www.tekniskamuseet.se/templates/Page.aspx?id=12447 |date=3 July 2009 }}</ref>

<ref name=twow2012>{{Cite news|url=http://mentalfloss.com/article/12969/how-do-two-way-mirrors-work|title=How Do Two-Way Mirrors Work?|date=2 November 2012|access-date=31 July 2017|language=en|archive-date=1 August 2017|archive-url=https://web.archive.org/web/20170801072830/http://mentalfloss.com/article/12969/how-do-two-way-mirrors-work|url-status=live}}</ref>

<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|access-date=23 August 2011|issn=0041-5278|archive-date=4 March 2016|archive-url=https://web.archive.org/web/20160304040209/http://unesdoc.unesco.org/images/0008/000817/081712eo.pdf|url-status=live}}</ref>

<ref name=ushw1979>{{Cite book|url=https://books.google.com/books?id=MZuEsb9Xk5kC|title=Assessment of Vehicle Safety Problems for Special Driving Populations: Final Report|date=1979|publisher=U.S. National Highway Traffic Safety Administration|language=en}}</ref>

<ref name=vdara2010>{{cite web|url = http://www.reviewjournal.com/news/vdara-visitor-death-ray-scorched-hair|title = Vdara visitor: 'Death ray' scorched hair|date = 25 September 2010|access-date = 13 September 2013|archive-date = 10 September 2013|archive-url = https://web.archive.org/web/20130910205841/http://www.reviewjournal.com/news/vdara-visitor-death-ray-scorched-hair|url-status = live}}</ref>

<ref name=walk1998>Bruce H. Walker (1998): ''Optical Engineering Fundamentals''. Spie Optical Engineering Press</ref>

<ref name=warn>{{cite book |title=The SAGE Handbook of Remote Sensing |first1=Timothy A. |last1=Warner |first2=M. Duane |last2=Nellis |first3=Giles M. |last3=Foody |publisher=SAGE |pages=349–350}}</ref>

<ref name=whit2013>{{Cite book|url=https://books.google.com/books?id=XkV9CgAAQBAJ&pg=PT92|title=Elements of Interior Design And Decoration|last=Whiton|first=Sherrill|date=16 April 2013|publisher=Read Books Ltd|isbn=978-1-4474-9823-0|language=en}}</ref>

<ref name=wild2010>{{cite web|url=http://www.sparknotes.com/lit/doriangray/|work=Sparknotes.com|title=''The Picture of Dorian Gray''|access-date=20 November 2010|archive-date=6 December 2010|archive-url=https://web.archive.org/web/20101206125454/http://www.sparknotes.com/lit/doriangray/|url-status=live}}</ref>

}}

== Further reading ==
* ''Le miroir: révélations, science-fiction et fallacies. Essai sur une légende scientifique'', Jurgis Baltrušaitis, Paris, 1978. {{ISBN|2-02-004985-6}}.
* ''On reflection'', [[Jonathan Miller]], National Gallery Publications Limited (1998). {{ISBN|0-300-07713-0}}.
* ''Lo specchio, la strega e il quadrante. Vetrai, orologiai e rappresentazioni del 'principium individuationis' dal Medioevo all'Età moderna'', [[Francesco Tigani]], Roma, 2012. {{ISBN|978-88-548-4876-4}}.
*Shrum, Rebecca K. 2017. ''[https://jhupbooks.press.jhu.edu/title/looking-glass In the Looking Glass: Mirrors and Identity in Early America] {{Webarchive|url=https://web.archive.org/web/20210502141856/https://jhupbooks.press.jhu.edu/title/looking-glass |date=2 May 2021 }}''. Johns Hopkins University Press.

== External links ==
{{Wiktionary|mirror}}
{{Wikiquote}}
*{{Commons category-inline|Mirrors}}
*{{cite EB1911|wstitle=Mirror|volume=18|pages=575–577}}
* {{usurped|1=[https://web.archive.org/web/20150214231103/http://mirrorlink.org/tech/manufacture.htm ''Mirror Manufacturing and Composition'', Mirrorlink]}}
* {{YouTube|8Y-kWGe01jE|Video of Mirror Making}}
* [https://web.archive.org/web/20071130004837/http://www.glasswebsite.com/video/mirror.asp How Mirrors Are Made (video)], Glass Association of North America (GANA)
* [https://longreads.com/2019/07/11/the-ugly-history-of-beautiful-things-mirrors/ July 2019 "The Ugly History of Beautiful Things: Mirrors" by Katy Kelleher for Longreads] {{Webarchive|url=https://web.archive.org/web/20190711163908/https://longreads.com/2019/07/11/the-ugly-history-of-beautiful-things-mirrors/ |date=11 July 2019 }}

{{Prehistoric technology |state=expanded}}

{{Authority control}}

[[Category:Fiction about mirrors]]
[[Category:Mirrors| ]]
[[Category:Glass applications]]
[[Category:Reflective building components]]
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