Total Internal Reflection全内反射(英文版).ppt

《Total Internal Reflection全内反射(英文版).ppt》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、TotalinternalreflectionThepictureshowstheimageofaboyformedbyaglass.theglasssurfaceisnotsmoothenough.onlyverysmallamountoflightisreflectedbytheglass.theenvironmentoutsideisnotdarkenough.lightrayshouldundergorefractioninsteadofreflection.dimimageIntroductionTheinsidesurfaceofwateroraglassblockca

2、nactlikeamirror.TotalinternalreflectionVideoSimulation1InternalreflectionAlightrayhitstheinsidefaceofasemicircularblockasfollows.Whatwillhappen?airglass1InternalreflectionTheincidentraysplitsinto2rays.angleofrefraction<90oincidentrayreflectedrayrefractedrayairglassForasmallangleofincidence1Inte

3、rnalreflectionincidentrayreflectedrayairglassCCasangleofincidence,angleofrefractioneventually,angleofrefraction=90refractedrayangleofincidence=criticalangleC1Internalreflectionnorefractedrayreflectedrayairglassangleofincidencecontinuesto,incidentray1InternalreflectionTherefore,ifangleofinci

4、dence>C,thelightrayistotallyreflectedinside.reflectedrayairglassincidentrayThisiscalledtotalinternalreflection.1InternalreflectionVideoCriticalangleandrefractiveindexincidentrayreflectedrayairglassCCrefractedraysin90osinCn=1sinCn=C=sin1or1n()Criticalangleandrefractiveindexcriticalanglesofdiff

5、erentmaterialsMediumRefractiveindexCriticalangle1.50–1.7030–42GlassWaterPerspexDiamond1.33491.5422.4224ExamplesoftotalinternalReflectionaPrismsinopticalinstrumentsplanemirror=glass+silveredsurfaceglasssheetsilveredsurfaceformstheimageI1I2I3Oobjectmultiplereflectioninsidetheglassmultipleima

6、gesformednuisanceinopticalinstruments4545Iflightraysstriketheinsidefaceatanangle>42,glassprismbehaveslikeaperfectmirror.45454545Prismsareusedasmirrorsinperiscopesandbinoculars.Insingle-lensreflexcameraAfive-sided‘pentaprism’reflectslightfromthemirrorintotheeye.filmmirror3Examplesoftotali

7、nternalreflectionbMirageOnadryroad.Inadesert.3ExamplesoftotalinternalreflectionbMirageHurray!Onahotday,youmayseeapoolofwateratadistanceinadesert.Sorry!WhatyouseeisjustaMIRAGE.Ithappensduetototalinternalreflections.layersofairneart