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词汇RayOptics射线光学Refraction折射Reflection反射IndexofRefraction折射率Opticalspectrum光谱Dispersion色散lens透镜TotalInternalReflection全内反射Prisms棱镜rightisoscelestriangles正等腰三角形 Sphericalrefractingsurface球面折射面signconvention 符号法则 paraxialapproximation 近轴近似 aberration像差chromaticaberration色差 collimated 平行的;使平行 criticalangle临界角 defect 缺点,缺陷 incident 入射的 inclination 倾斜角;偏向 magnitude 数量级 virtualimage虚像Diffraction衍射Interference干涉aperture孔径complexexponentialfunction复指数函数complexconjugate 复共轭 monochromatic 单色的 opticalpathdifference光程差polarization偏振resonator谐振器resolution分辨率Holography全息术wavelength波长microscope显微镜beamsplitter分束器Rainbowholography彩虹全息术Volumeholograms体全息图Computer-generatedholography计算机全息术SpatialFiltering空间滤波gratings光栅
harmonicsinterferogram谐波干涉图pupilfunction光瞳函数principalmaxima主极大值ModeLocking波模锁定;振荡型同步Transversemodes横向模式Laserrangefinder激光测距仪navigation导航Photodetector光电检测器photomultiplier光电倍增管Photon光子OpticalFiberCommunication光纤通信fiber纤维OpticalLoss光学损失Group集体velocity速度nonlinearity非线性anomalous-dispersion反常色散StimulatedRamanScattering受激拉曼散射Self-PhaseModulation相位调制效应Cross-PhaseModulation交叉相位调制bandwidth带宽opticalswitches光开关Photodetectors光电探测器crystal晶体Birefringence双折射electron电子Mechanicalandthermalstrength机械和热强度surface表面Bandgap能带carrierconcentration载体浓度discharge放电photovoltaic光伏OpticalThinFilmTechnology光学薄膜技术Photolithography光刻,biophotonics生物光子学,3DDisplayTechnology3d显示技术,InfraredDetectionTechnology红外探测技术
exposure曝光irradiation辐照nanoparticle纳米颗粒句子Wetreatlightbeamsasraysthatpropagatealongstraightlines,exceptatinterfacesbetweendissimilarmaterials,wheretheraysmaybebentorrefracted.Thisapproach,whichhadbeenassumedtobecompletelyaccuratebeforethediscoveryofthewavenatureoflight,leadstoagreatmanyusefulresultsregardinglensopticsandopticalinstruments.我们将光束处理为沿着直线传播的光线,除了在不同材料之间的界面处,其中光线可以被弯曲或折射。这种方法被认为在发现光的波特性之前是完全准确的,导致产生许多关于透镜光学和光学仪器的有用结果。Whenalightraystrikesasmoothinterfacebetweentwotransparentmediaatanangle,itisrefracted.当光线以一个角度撞击在两个透明介质之间的平滑界面时,其为折射。Therefractiveindexofagivenmaterialisnotindependentofwavelength,butgenerallyincreasesslightlywithdecreasingwavelength.给定材料的折射率并非与波长无关,但通常随着波长减小而略微增加。Awordofwarningwithregardtothesignsinalgebraicexpression:Becauseofthesignconventionadoptedhere,derivationsbasedsolelyongeometrywillnotnecessarilyresultinthecorrectsignforagiventerm.Therearetwowaystocorrectthisdefect.Thefirst,tocarryaminussignbeforethesymbolofeachnegativequantity,istoocumbersomeandconfusingforgeneraluse.Thus,weadoptthesecond,whichistogothroughthefinalformulaandchangethesignofeachnegativequantity.Thisprocedurehasalreadybeenadoptedinconnectionwiththe“len”equationandisnecessary,asnoted,tomaketheformulaalgebraicallycorrect.Itisimportant,though,nottochangethesignsuntilthefinalstep,lestsomesignsbealteredtwice.关于代数表达式中的符号的警告词:由于这里采用的符号法则,仅基于几何的导出不一定导致给定术语的正确符号。有两种方法来纠正此缺陷。第一,在每个负数量的符号之前携带减号,对于一般使用来说太麻烦和混乱。因此,我们采用第二个,即通过最后的公式,并改变每个负数量的符号。这个程序已经结合“len”方程被采用,并且如上所述是必要的,以使公式在代数上是正确的。然而,重要的是,不要改变迹象,直到最后一步,以免一些迹象改变两次。Whenconditionsaresuchthatthelightisincoherent,itisnotpossibletodetectinterferenceeffects.Adiscussionofwaveopticsisincompletewithoutconsideringtheconditionsthatmustexistforaninterferenceexperimenttobeperformedsuccessfully.
当条件使得光不相干时,不可能检测干涉效应。波光学的讨论是不完整的,没有考虑必须存在的条件,以便干扰实验成功地执行。Lightisatransverse,electromagneticwavecharacterizedbytime-varyingelectricandmagneticfields.Thefieldspropagatehandinhand;itisusuallysufficienttoconsidereitheroneandignoretheother.Itisconventionaltoretaintheelectricfield,largelybecauseitsinteractionwithmatterisinmostcasesfarstrongerthanthatofthemagneticfield.光是以时变的电场和磁场为特征的横向电磁波。在领域里携手共进;通常足以考虑一个而忽略另一个。通常保持电场,主要是因为其与物质的相互作用在大多数情况下远远强于磁场的相互作用。Atransversewave,likethewaveonapluckedstring,vibratesatrightanglestothedirectionofpropagation.Suchawavemustbedescribedwithvectornotation,becauseitsvibrationhasaspecificdirectionassociatedwithit.Forexample,thewavemayvibratehorizontally,vertically,orinanyotherdirection;oritmayvibrateinacomplicatedcombinationofhorizontalandverticaloscillations.Sucheffectsarecalledpolarizationeffects.Awavethatvibratesinasingleplane(horizontal,forexample)issaidtobeplanepolarized.横波,类似于拾取弦上的波,以与传播方向成直角振动。这样的波必须用矢量符号来描述,因为它的振动具有与其相关联的特定方向。例如,波可以水平地,垂直地或在任何其它方向上振动;或者其可以以水平和垂直振荡的复杂组合振动。这种效应称为偏振效应。在单个平面(例如水平)中振动的波被称为平面偏振。Spectralfiltersaredevicesusedtomodifythe(spectral)transmittanceofanopticalsystem.Theymaybemadeofahomogeneousmaterialwithappropriatespectralabsorptioncharacteristics,oruseotheropticalphenomenon,suchasmultiple-beaminterferenceoropticalanisotropy,toeffectthemodification.光谱滤光器是用于修改光学系统的(光谱)透射率的装置。它们可以由具有适当光谱吸收特性的均匀材料制成,或者使用其它光学现象,例如多光束干涉或光学各向异性,以实现修改。Thefifthgenerationoflightwavesystemsemployserbium-dopedfiberamplifiersforamplifyingthetransmittedopticalsignalperiodicallytocompensateforfiberloss.第五代光波系统采用掺铒光纤放大器来周期性地放大传输的光信号,以补偿光纤损耗。Asopticalmedia,crystalsaremuchlesspopularthanglassesfortheobviousreasonthattheyarefarmoredifficulttomanufactureinlargesize.Theiruseisinvariablymotivatedbytheneedforcharacteristicsnotreadilyobtainableinglass.Amongthesecharacteristicsarethefollowing:(1)Spectraltransmittancecharacteristicsextendingbeyondthoseobtainablewiththeusualglasses;(2)Specialshapeofthedispersioncurve;(3)Birefringence,electro-,andmagnetoopticalcharacteristics;(4)Mechanicalandthermalstrength.
作为光学介质,由于明显的原因,晶体比玻璃更不受欢迎,因为它们在大尺寸下难以制造。它们的使用总是由对玻璃中不容易获得的特性的需要所驱动。这些特性如下:(1)超过用通常的玻璃获得的光谱透射率特性;(2)分散曲线的特殊形状;(3)双折射,电光和磁光特性;(4)机械和热强度。Forthesepotentialadvantagestoberealized,waysmustbefoundtoproducehighlycompactcomponents:(1)Opticalwaveguideswhosecross-sectionaldimensionsareindeedoftheorderofmagnitudeofanopticalwavelength.(2)Lightsourcesanddetectorsofsimilardimensions.(3)Lightmodulationandsteeringdevicesofasizeconsistentwith(1)and(2).为实现这些潜在优势,必须找到方法来产生高度紧凑的组件:(1)光波导的横截面尺寸数量级的确实是一个光学波长。(2)光源和探测器类似的维度。(3)光调制和操舵装置的大小与(1)和(2)一致。However,toobtainhighefficiencies,alowworkfunctiondoesnotsuffice;thecathodemustbesuchthatusefulphotoexitationcantakeplacealsowithinthematerialuptothedepthofseveraltensofnanometers.然而,为了获得高效率,低功函数不足;阴极必须使得有用的光激发也可以在材料内发生达到几十纳米的深度。Photoconductivedetectorsfallintotwomajorcategories:(1)Homogeneousdetectorswhereacarrier,freedanywhereinsidethematerialisdrawnoutbyanexternallyappliedfield.(2)Junctiondetectors,wherethecarriersaregeneratedintheneighborhoodofap-njunctiontobeseparatedbyaninternallygeneratedfield.光电导检测器分为两个主要类别:(1)均匀检测器,其中在材料内任何地方释放的载体由外部施加的场引出。(2)结检测器,其中载流子在p-n结附近产生以由内部产生的场分离。Thethermaldetectorsrespondduetoachangeintemperaturewhichisafunctionoftheabsorbedenergyandindependentofitswavelength;theirspectralresponseisdeterminedsolelybytheirspectralabsorptivityandisthereforegenerallymuchmoreuniformthanthatobtainedwithasimplephotondetector.热检测器由于温度变化而响应,该温度变化是吸收能量的函数并且与其波长无关;它们的光谱响应仅由它们的光谱吸收率确定,因此通常比用简单的光子检测器获得的光谱响应更均匀。Opticalthinfilmsarewidelyusedtodayinmanydiverseapplicationstocontrolthewaylightisreflected,transmitted,orabsorbedasafunctionofwavelength.Theycanbegroupedintotwomajorcategoriesbasedontheapplication.Inthefirst,thelighttravelsparalleltotheplaneofthesubstratewiththefilmsactingaswaveguidesintheemergingfieldofintegratedoptics.Herelightsignalscouldreplaceelectricalsignalsinapplicationssuchascommunicationsandcomputers.Inthesecondapplication,thelighttravelsperpendiculartothefilmplaneforuseasantireflectioncoatings,edgefilters,highefficiencymirrors,beamsplitters,etc.
光学薄膜目前在许多不同的应用中广泛使用,以控制光作为波长的函数被反射,透射或吸收的方式。根据应用,它们可以分为两大类。在第一种情况下,光平行于衬底的平面传播,其中膜用作集成光学器件的出射场中的波导。这里,光信号可以替代诸如通信和计算机的应用中的电信号。在第二应用中,光垂直于膜平面行进,用作抗反射涂层,边缘滤光器,高效率反射镜,分束器等。Theterm“thin”isusedtoindicatealayerwhosethickness(perpendiculartothesubstrate)isthesameorderofmagnitudeasthewavelengthofinterest,andtheextent(paralleltothesubstrate)isaverylargenumberofwavelengths.Typicallayersmightrangeinthicknessfrom80nminthevisibletotwentytimesthatintheinfrared.Filtersarecomposedofastackofsuchlayers,alternatingbetweenhighandlowrefractiveindices,withtypically20~40layers,althoughinsomecasestheymayhaveonehundredlayersormore.Thinfilmfiltersoperatebyinterferenceofthelightreflectedfromthevariouslayersasthelightpassesthroughperpendiculartothesubstrate.术语“薄”用于表示其厚度(垂直于衬底)与感兴趣的波长具有相同数量级的层,并且(与衬底平行)的程度是非常大量的波长。典型的层的厚度可以在从可见光的80nm到红外的20倍的范围内。滤光器由这样的层的堆叠组成,在高折射率和低折射率之间交替,通常具有20〜40层,但是在一些情况下,它们可以具有一百层或更多层。当光垂直于衬底通过时,薄膜滤波器通过从各个层反射的光的干涉来操作。Photolithography,oropticallithographyisaprocessusedinmicrofabricationtoselectivelyremovepartsofathinfilmorthebulkofasubstrate.Ituseslighttotransferageometricpatternfromaphotomasktoalight-sensitivechemicalphotoresist,orsimplyresist,onthesubstrate.光刻或光学光刻是在微加工中使用以选择性地移除薄膜的一部分或基板的主体的工艺。它使用光将几何图案从光掩模转移到基底上的光敏化学光致抗蚀剂或简单地抗蚀剂。