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| [[Image:Coating-Mirror-Lens.jpg|frame|right|Optically coated mirrors and lenses.]]
| | == は隠れ場所をしている、か == |
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| An '''optical coating''' is one or more [[thin-film optics|thin layer]]s of material deposited on an optical component such as a [[lens (optics)|lens]] or [[mirror]], which alters the way in which the optic [[Reflection (physics)|reflects]] and [[transmission (telecommunications)|transmits]] light. One type of optical coating is an [[Anti-reflective coating|antireflection coating]], which reduces unwanted reflections from surfaces, and is commonly used on [[glasses|spectacle]] and [[photographic lens]]es. Another type is the '''high-reflector coating''' which can be used to produce mirrors which reflect greater than 99.99% of the light which falls on them. More complex optical coatings exhibit high reflection over some range of [[wavelength]]s, and anti-reflection over another range, allowing the production of [[dichroism|dichroic]] [[thin-film optical filters]].
| | ナ[OK]を、Geはよだれ助けないJige参照してください [http://www.dmwai.com/webalizer/kate-spade-7.html ケイトスペード 財布 通販]。<br><br>は隠れ場所をしている、か？<br>二階に彼自身の考えにショックを受け、犯罪、より<br>、最後にチャンネルを歩き、ウェイターが、一見配布ルームと部屋に、クラッターの床を引く、パスをまっすぐうなずいたとき大手層の下に [http://www.dmwai.com/webalizer/kate-spade-6.html kate spade マザーズバッグ]......階下、左折停止する黒グー真冬の場所で、廊下に、左折して、カチャカチャという音が続き、小さな鉄の門が開きます [http://www.dmwai.com/webalizer/kate-spade-10.html ケイトスペード バッグ ショルダー]。ラッシュが来た何の外の雨を注ぐ [http://www.dmwai.com/webalizer/kate-spade-4.html ケイトスペード 時計 取り扱い店]。<br><br>は、実際に4つの中古品に出願された鄭チャオが車に急いで、暗い、車を待っている、鄭チャオが車の前に座って、車のサンウ音が始まった。<br><br>引っ張られるかを知ることができる人、言うまでもありませんが、暗室に保管されている、私は秘密のドアの外から、うろついサウナの中にある、唖然罪なので、巡航方向のも、彼の感覚なかったどの場所？<br><br>「ここに、全く換気を喫煙しないでください [http://www.dmwai.com/webalizer/kate-spade-1.html ケイトスペード 財布 店舗]。「粉末点火ツァイはちょうど、大きなお尻は、大きなお尻を吸うためにあえて文章を批判した。私は犯罪を比較し、その3、長い間、私の罪のために、実際には非常に静か |
| | 相关的主题文章： |
| | <ul> |
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| | <li>[http://www.bibk.nu/cgi-bin/guestbook_f96/guestbook.cgi http://www.bibk.nu/cgi-bin/guestbook_f96/guestbook.cgi]</li> |
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| | <li>[http://www.mattia.ca/cgi-bin/newsboard.cgi http://www.mattia.ca/cgi-bin/newsboard.cgi]</li> |
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| | <li>[http://e-hp.info/mitsuike/4-bbs/bbs/m-123y.cgi http://e-hp.info/mitsuike/4-bbs/bbs/m-123y.cgi]</li> |
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| | </ul> |
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| ==Types of coating== | | == またはので、彼女は非常にショックを受けた == |
| [[Image:Image-Metal-reflectance.png|thumb|350px|Reflectance vs. wavelength curves for aluminium (Al), silver (Ag), and gold (Au) metal mirrors at normal incidence]]
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| The simplest optical coatings are thin layers of [[metal]]s, such as [[aluminium]], which are deposited on glass substrates to make mirror surfaces, a process known as [[silvering]]. The metal used determines the reflection characteristics of the mirror; aluminium is the cheapest and most common coating, and yields a reflectivity of around 88%-92% over the [[visible spectrum]]. More expensive is [[silver]], which has a reflectivity of 95%-99% even into the far [[infrared]], but suffers from decreasing reflectivity (<90%) in the blue and [[ultraviolet]] spectral regions. Most expensive is [[gold]], which gives excellent (98%-99%) reflectivity throughout the [[infrared]], but limited reflectivity at wavelengths shorter than 550 [[nanometre|nm]], resulting in the typical gold colour.
| | 'まあ、ああ、あなたを呼び出す......あなたを教えて？'<br><br>「男どのように？ [http://www.dmwai.com/webalizer/kate-spade-14.html kate spade マザーズバッグ] '<br><br>'ハハッハッハ......あなたはハンサムであると思いますか？'<br><br>「間違いなく、省略、男を呼びの前で男ではありません。 [http://www.dmwai.com/webalizer/kate-spade-5.html ケイトスペードのバッグ] '<br>「ハッハッハ......それは男自身、その警察の男、あなたは忘れてはいけないことを、ああ、私に食事を作ることを約束した日と呼ばれている。」<br><br>「私は何の問題をしない毎日、あなたはああに招待された美しさを恐れていないよ。」<br><br><br>「そのことについて今日は？ '<br>「 [http://www.dmwai.com/webalizer/kate-spade-1.html ケイトスペード マザーズバッグ].........、二十四時間のスタンバイを呼ぶ」<br><br>2物質の言葉に、インターコンチネンタルホテルのレストランに設定作業から午後に予定Niwai、、、Niwai [http://www.dmwai.com/webalizer/kate-spade-10.html ケイトスペード バッグ ショルダー] 10分の間<br>、オーディオカットXiaomeng [http://www.dmwai.com/webalizer/kate-spade-11.html ケイトスペード 財布 通販] Qiは彼の下唇を噛ん、本当に男そう恥知らずな極端な側面を参照してください。またはので、彼女は非常にショックを受けた。<br><br>「これは小さな若いPaoniuの一種の伝説とは？」でも赤市が彼の頬に傷をつけ、霧が聞こえ、それが彼のシークレットサービスの考え方に反している。 |
| | 相关的主题文章： |
| | <ul> |
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| | <li>[http://www.zxmrzn.com/home.php?mod=space&uid=209146 http://www.zxmrzn.com/home.php?mod=space&uid=209146]</li> |
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| | <li>[http://www.d1km.com/home.php?mod=space&uid=23622 http://www.d1km.com/home.php?mod=space&uid=23622]</li> |
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| | <li>[http://www.wenxuelu.com/home.php?mod=space&uid=183243 http://www.wenxuelu.com/home.php?mod=space&uid=183243]</li> |
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| | </ul> |
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| By controlling the thickness and density of metal coatings, it is possible to decrease the reflectivity and increase the transmission of the surface, resulting in a ''[[half-silvered mirror]]''. These are sometimes used as "[[one-way mirror]]s".
| | == 「さあ、私の車を取る == |
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| The other major type of optical coating is the [[dielectric]] coating (i.e. using materials with a different refractive index to the substrate). These are constructed from thin layers of materials such as [[magnesium fluoride]], [[calcium fluoride]], and various metal oxides, which are deposited onto the optical substrate. By careful choice of the exact composition, thickness, and number of these layers, it is possible to tailor the reflectivity and transmitivity of the coating to produce almost any desired characteristic. Reflection coefficients of surfaces can be reduced to less than 0.2%, producing an ''antireflection'' (AR) coating. Conversely, the reflectivity can be increased to greater than 99.99%, producing a ''high-reflector'' (HR) coating. The level of reflectivity can also be tuned to any particular value, for instance to produce a mirror that reflects 90% and transmits 10% of the light that falls on it, over some range of wavelengths. Such mirrors are often used as [[beamsplitter]]s, and as [[output coupler]]s in [[laser]]s. Alternatively, the coating can be designed such that the mirror reflects light only in a narrow band of wavelengths, producing an [[filter (optics)|optical filter]].
| | あなたが彼を見て、それはマウスを忘れて......ああ自分自身を楽しむことが見えることを発見するだけ会っていた、慰めの道を食べる必要がないようにしてください。 '<br><br>「もう、白のケアです。、私たちは行きます [http://www.dmwai.com/webalizer/kate-spade-2.html マザーズバッグ ケイトスペード]。「熊Jianfei道路 [http://www.dmwai.com/webalizer/kate-spade-9.html ケイトスペード リボン バッグ]。<br>外出先で話し<br>3人が、この犯罪はとき、私は停止に追いつく、気になるようになります。集まって、私たちは一緒になる...... [http://www.dmwai.com/webalizer/kate-spade-1.html ケイトスペード 財布 セール] 'ください媒介されない、それは実際にいくつかのサブ里ではないことを、上と呼ばシュシュ会った。 '<br><br>「さあ、私の車を取る [http://www.dmwai.com/webalizer/kate-spade-8.html 財布 ケイトスペード]。「熊Jianfeiを私が罪を犯す抱擁は、彼らが車に向かって歩いて笑って、肩でお互いを破った。<br>まだその知らせに笑顔、目自体を作るためにXiaomengチーとマウスの後ろ<br> [http://www.dmwai.com/webalizer/kate-spade-9.html ケイトスペードバッグセール]。<br><br>しかし、その後、それYuebuqilai、長い卒業し、学生間の接触後に、学ぶためにドンShaojun、より疎外、場合のリー第冬でも、食いしん坊サン李と呉Guangyuも自分自身を開いて、接触しない他よりも麻薬に忙しい豆暁波は、戻っていなかったの半分を持っています。電話スタッブスは、私の罪とマウスは落胆が、幸い、隊漢王シェンジェンにリンクされていた |
| | 相关的主题文章： |
| | <ul> |
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| | <li>[http://www.liberalismen.dk/index.cgi http://www.liberalismen.dk/index.cgi]</li> |
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| | <li>[http://www.cqwkc.net/forum.php?mod=viewthread&tid=128659&extra= http://www.cqwkc.net/forum.php?mod=viewthread&tid=128659&extra=]</li> |
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| | <li>[http://www.carmtcpj.com/sns/space.php?uid=2741&do=blog&id=9037 http://www.carmtcpj.com/sns/space.php?uid=2741&do=blog&id=9037]</li> |
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| | </ul> |
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| The versatility of dielectric coatings leads to their use in many scientific optical instruments (such as lasers, [[Microscope|optical microscope]]s, [[refracting telescope]]s, and [[interferometry|interferometer]]s) as well as consumer devices such as [[binoculars]], spectacles, and photographic lenses.
| | == 人をキャッチする二時間 == |
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| Dielectric layers are sometimes applied over top of metal films, either to provide a protective layer (as in [[silicon dioxide]] over aluminium), or to enhance the reflectivity of the metal film. Metal and dielectric combinations are also used to make advanced coatings that cannot be made any other way. One example is the so-called "[[perfect mirror]]", which exhibits high (but not perfect) reflection, with unusually low sensitivity to wavelength, angle, and [[Polarization (waves)|polarization]].<ref>{{cite web|url=http://web.mit.edu/newsoffice/nr/1998/mirror.html|title=MIT researchers create a 'perfect mirror' | work=MIT press release |date=1998-11-26 |accessdate=2007-01-17}}</ref>
| | 私たちは、ドキュメントを検索し、セキュリティエリアを所有される前に、殺人は一緒に発生したか、数百ドルするため、仲介者への出稼ぎが刺さ。人をキャッチする二時間。 [http://www.dmwai.com/webalizer/kate-spade-8.html 財布 ケイトスペード] 'マウスの道。<br><br>「動機が満たさ単純で、お金が単語であるが、ターゲットを見つけるために、それは自分自身でした。」Xiaomeng [http://www.dmwai.com/webalizer/kate-spade-0.html ケイトスペード 人気 財布] Qiは、微笑んで遠くのものから変わった。<br>これは、マウスの心臓笑顔、で彼の斜め目指し、場合について楽しむための良い方法を反映し<br>、彼はあまり考えていませんでした [http://www.dmwai.com/webalizer/kate-spade-0.html ケイトスペード中古バッグ]。<br>すぐに目的地までの<br>、一等地でアリュールの美しさ、美容室、クラブ制度、劉翔と呼ばれ、駐車場不足、ほとんど混血車を運転、ゆっくりと歩いて、道端で停止車3が眉をひそめた時、この場所は、乗客のフロントフードのトリックを開くことが不可能だ [http://www.dmwai.com/webalizer/kate-spade-7.html ケイトスペード 財布 通販]。<br><br>「20メートル離れた場所の美しさから、クラブで駐車し、彼女の車が、午後になると、サロンで三時間を過ごした。」Xiaomeng [http://www.dmwai.com/webalizer/kate-spade-13.html ケイトスペード 人気バッグ] Qiは場所を指摘し、その場所には車を詰め、住宅の入り口に直面している。<br><br>「これは持って |
| | | 相关的主题文章： |
| ===Antireflection coatings===
| | <ul> |
| {{main|Anti-reflective coating}}
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| [[Image:Anti-reflective coating comparison.jpg|thumb|right|150px|Comparison of uncoated glasses (top) and glasses with an anti-reflective coating (bottom).]]
| | <li>[http://www.urbandead.com/signup.cgi http://www.urbandead.com/signup.cgi]</li> |
| Antireflection coatings are used to reduce reflection from surfaces. Whenever a [[ray (optics)|ray]] of light moves from one [[Medium (optics)|medium]] to another (such as when light enters a sheet of [[glass]] after travelling through [[air]]), some portion of the light is reflected from the surface (known as the ''interface'') between the two media.
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| | | <li>[http://www.mbrsecurity.com/forum/index.php?topic=194234.msg211544#msg211544 http://www.mbrsecurity.com/forum/index.php?topic=194234.msg211544#msg211544]</li> |
| A number of different effects are used to reduce reflection. The simplest is to use a thin layer of material at the interface, with an index of refraction between those of the two media. The reflection is minimized when
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| :<math>n_1 = \sqrt{n_0 n_S}</math>,
| | <li>[http://www.nibiye.com/plus/feedback.php?aid=10759 http://www.nibiye.com/plus/feedback.php?aid=10759]</li> |
| where <math>n_1</math> is the index of the thin layer, and <math>n_0</math> and <math>n_S</math> are the indices of the two media. The optimum refractive indices for multiple coating layers at angles of incidence other than 0° is given by Moreno et al. (2005).<ref>{{cite web|url=http://planck.reduaz.mx/~imoreno/Publicaciones/OptLett2005.pdf|title=''Thin-film spatial filters'',|format=PDF|accessdate=2007-05-30}}</ref>
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| | | </ul> |
| Such coatings can reduce the reflection for ordinary glass from about 4% per surface to around 2%. These were the first type of antireflection coating known, having been discovered by [[John William Strutt, 3rd Baron Rayleigh|Lord Rayleigh]] in 1886. He found that old, slightly tarnished pieces of glass transmitted more light than new, clean pieces due to this effect.
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| Practical antireflection coatings rely on an intermediate layer not only for its direct reduction of reflection coefficient, but also use the [[Interference (wave propagation)|interference]] effect of a thin layer. If the layer's thickness is controlled precisely such that it is exactly one-quarter of the wavelength of the light (a ''quarter-wave coating''), the reflections from the front and back sides of the thin layer will destructively interfere and cancel each other.
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| [[Image:Optical-coating-2.png|right|thumb|Interference in a quarter-wave antireflection coating]]
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| In practice, the performance of a simple one-layer interference coating is limited by the fact that the reflections only exactly cancel for one wavelength of light at one angle, and by difficulties finding suitable materials. For ordinary glass (''n''≈1.5), the optimum coating index is ''n''≈1.23. Few useful substances have the required refractive index. [[Magnesium fluoride]] (MgF<sub>2</sub>) is often used, since it is hard-wearing and can be easily applied to substrates using [[physical vapor deposition|physical vapour deposition]], even though its index is higher than desirable (n=1.38). With such coatings, reflection as low as 1% can be achieved on common glass, and better results can be obtained on higher index media.
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| Further reduction is possible by using multiple coating layers, designed such that reflections from the surfaces undergo maximum destructive interference. By using two or more layers, broadband antireflection coatings which cover the visible range (400-700 nm) with maximum reflectivities of less than 0.5% are commonly achievable. Reflection in narrower wavelength bands can be as low as 0.1%. Alternatively, a series of layers with small differences in refractive index can be used to create a broadband antireflective coating by means of a [[gradient-index optics|refractive index gradient]].
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| ===High-reflection coatings===<!-- This section is linked from [[Laser construction]] -->
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| {{seealso|Dielectric mirror}}
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| High-reflection (HR) coatings work the opposite way to antireflection coatings. The general idea is usually based on the periodic layer system composed from two materials, one with a high index, such as [[zinc sulfide]] (''n''=2.32) or [[titanium dioxide]] (''n''=2.4) and low index material, such as [[magnesium fluoride]] (''n''=1.38) or [[silicon dioxide]] (''n''=1.49). This periodic system significantly enhances the reflectivity of the surface in the certain wavelength range called [[band-stop]], whose width is determined by the ratio of the two used indices only (for quarter-wave system), while the maximum reflectivity is increasing nearly up to 100% with a number of layers in the ''stack''. The thicknesses of the layers are generally quarter-wave (then they yield to the broadest high reflection band in compare to the non-quarter-wave systems composed from the same materials), this time designed such that reflected beams ''constructively'' interfere with one another to maximize reflection and minimize transmission. The best of these coatings built-up from deposited dielectric lossless materials on the perfect smooth surfaces can reach reflectivities greater than 99.999% (over a fairly narrow range of wavelengths). Common HR coatings can achieve 99.9% reflectivity over a broad wavelength range (tens of nanometers in the visible spectrum range).
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| As for AR coatings, HR coatings are affected by the incidence angle of the light. When used away from normal incidence, the reflective range shifts to shorter wavelengths, and becomes polarization dependent. This effect can be exploited to produce coatings that polarize a light beam.
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| By manipulating the exact thickness and composition of the layers in the reflective stack, the reflection characteristics can be tuned to a particular application, and may incorporate both high-reflective and anti-reflective wavelength regions. The coating can be designed as a long- or short-pass filter, a bandpass or notch filter, or a mirror with a specific reflectivity (useful in lasers). For example, the [[dichroic prism]] assembly used in some [[camera]]s requires two dielectric coatings, one long-wavelength pass filter reflecting light below 500 nm (to separate the blue component of the light), and one short-pass filter to reflect red light, above 600 nm wavelength. The remaining transmitted light is the green component.
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| ====Extreme ultraviolet coatings====
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| In the [[ultraviolet|EUV]] portion of the spectrum (wavelengths shorter than about 30 nm) nearly all materials absorb strongly, making it difficult to focus or otherwise manipulate light in this wavelength range. Telescopes such as [[TRACE]] or [[Extreme ultraviolet Imaging Telescope|EIT]] that form images with EUV light use multilayer mirrors that are constructed of hundreds of alternating layers of a high-mass metal such as [[molybdenum]] or [[tungsten]], and a low-mass spacer such as [[silicon]], [[vacuum deposition|vacuum deposited]] onto a substrate such as [[glass]]. Each layer pair is designed to have a thickness equal to half the wavelength of light to be reflected. [[Constructive interference]] between scattered light from each layer causes the mirror to reflect EUV light of the desired wavelength as would a normal metal mirror in visible light. Using multilayer optics it is possible to reflect up to 70% of incident EUV light (at a particular wavelength chosen when the mirror is constructed).
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| ===Transparent conductive coatings===
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| Transparent [[electrical conduction|conductive]] coatings are used in applications where it is important that the coating conduct electricity or dissipate [[static electricity|static charge]]. Conductive coatings are used to protect the aperture from [[electromagnetic Interference]], while dissipative coatings are used to prevent the build-up of [[static electricity]]. Transparent conductive coatings are also used extensively to provide electrodes in situations where light is required to pass, for example in [[flat panel display]] technologies and in many [[photoelectrochemistry|photoelectrochemical]] experiments. A common substance used in transparent conductive coatings is [[indium tin oxide]] (ITO). ITO is not very optically transparent, however. The layers must be thin to provide substantial transparency, particularly at the blue end of the spectrum. Using ITO, [[sheet resistance]]s of 20 to 10,000 [[ohms per square]]<!--This strange unit is correct.--> can be achieved. An ITO coating may be combined with an antireflective coating to further improve [[transmittance]]. Other TCOs (Transparent Conductive Oxides) include AZO (Aluminium doped Zinc Oxide), which offers much better UV transmission than ITO.
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| A special class of transparent conductive coatings applies to infrared films for theater-air military optics where IR transparent windows need to have ([[Radar]]) stealth ([[Stealth technology]]) properties. These are known as RAITs (Radar Attenuating / Infrared Transmitting) and include materials such as boron doped DLC ([[Diamond-like carbon]]){{Citation needed|date=April 2013}}.
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| ==Sources==
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| * Hecht, Eugene. Chapter 9, ''Optics'', 2nd ed. (1990), Addison Wesley. ISBN 0-201-11609-X.
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| * I. Moreno, et al., "Thin-film spatial filters," ''Optics Letters'' 30, 914-916 (2005)
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| * C. Clark, et al., "Two-color Mach 3 IR coating for TAMD systems", Proc. SPIE Vol. 4375, p. 307-314 (2001)
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| ==References==
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| {{reflist}}
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| ==See also==
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| * [[List of telescope parts and construction]]
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| ==External links==
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| * [http://clearapertures.com/dopub/Design%20Online.html Browser-based thin film design and optimization software]
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| * [http://www.falstad.com/ripple/ex-coating.html Java demonstration of anti-reflection coating]
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| *[http://www.calctool.org/CALC/phys/optics/thin_film Browser-based numerical calculator of single-layer thin film reflectivity]
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| * [http://www.cvimellesgriot.com/Products/Documents/TechnicalGuide/Optical-Coatings.pdf Optical Coatings] - CVI Melles Griot Technical Guide
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| [[Category:Thin-film optics]]
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| [[de:Antireflexbeschichtung]]
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| [[ru:Просветление оптики]]
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