工程光学英语补充内容和习题.ppt

1 EnglishSummary 1 Theelectromagneticspectrum long short Wavelength 380nmviolet blue780nmdeep red 2 2 LawofRectilinearpropagation Lightasitadvancesthroughfreespaceorthroughhomogeneous isotropicmatterfollowsabeeline adirectstraightcourse Example Shadows 3 3 TheLawofReflection Alightraystrikingareflectingsurfaceandreflectedfromitmakesequalangleswiththenormaltothesurfaceatthepointofincidence I Iandtheincomingray theoutgoingray andthenormaltothesurfaceatthepointofintersectionalllieinthesameplane 4 4 TheLawofRefraction Theanglemadebytheincidentray thatmadebytherefractedray andthesurfacenormalatthepointofincidenceinarefractiveprocessobeytheexpressionnsinI n sinI Theincidentray therefractedray andthesurfacenormalareallcoplanar 5 5 TotalInternalReflection 6 Fermat principle Lighttakesthepaththatrequirestheleasttime 6 7 Keywordsandconcept Imagespaceextendsfrominfinityononesidetoinfinityontheother Thesameholdsfortheobjectspace bothcompletelyoverlap Whetheragivenpointisintheobjectspaceortheimagespacedependsonwhetheritispartofaraybeforeorafterrefraction Ifagivenpointisintheobjectspace itisapointobject otherwiseitisapointimage 7 Homework 1 Inancienttimestherectilinearpropagationoflightwasusedtomeasuretheheightofobjectsbycomparingthelengthoftheirshadowswiththelengthoftheshadowofanobjectofknownlength Astaff2mlongwhenhelderectcastsashadow3 4mlong whileabuilding sshadowis170mlong Howtallisthebuilding 2 Lightfromawatermediumwithn 1 33isincidentuponawater glassinterfaceatanangleof45o Theglassindexis1 50 Whatangledoesthelightmakewiththenormalintheglass P124 9 8 SomeKeywords 1 singlesphericalsurface2 convergeanddivergence3 conjugate points planes distanceetc 4 magnification transverse axial angular 5 Lagrange sinvariant6 signconvention vertex imagedistance 7 imagecharacteristics largerorsmaller uprightorinverted realorvirtual 8 Concaveandconvexmirror 9 1 Vertexisthepointwheretheopticaxisintersectsthesurface 2 Objectdistanceisthedistancefromvertextotheobject 3 Imagedistanceisthedistancefromvertextotheimage 4 Centerofcurvatureisthecenterofsinglesphericalsurface 5 Meridionalplaneisaplanecontainingtheopticaxisandtheobject SomeConcept 10 Homework 1 Agoldfishswims10cmfromthesideofasphericalbowlofwaterofradius20cm Wheredoesthefishappeartobe Doesitappearlargerorsmaller 2 Anobjectislocated2cmtotheleftofconvexendofaglassrodwhichhasaradiusofcurvatureof1cm Theindexofrefractionoftheglassisn 1 5 Findtheimagedistance P13 12 14 11 SomeKeywordsandconcept 1 Principalplanesaredefinedasthelociwhererefractionisassumedtooccurwithoutreferenceastowhereitactuallydoesoccur 2 Principalpointsarethepointswheretheopticalaxisintersectsprincipalplanes 3 Focalpoints thefirst thesecond theobject side theimage side 12 4 focallengthisthedistancefromtheprincipalpointtothefocalpoint 5 Aon axialpointobjectatinfinityandthesecondfocalpointareconjugate 13 Homework P18 Example 14 SomeKeywordsandconcept 1 Graphicalconstruction H H F F Focalray Chiefray Parallelray Theparallelrayisfirstparalleltotheaxisandthen afterrefractionpassesthroughF ThefocalraypassesthroughFandthenisrenderedparalleltotheaxis Thechiefraygoesthroughtheprincipalpointwithoutdeviation 15 SomeKeywordsandconcept 2 Newton slensequation x x arecalledNewton sextrafocalobjectandimagedistances respectively 3 Gauss equation 16 Homework 1 Anobject1cmhighis30cminfrontofathinlenswithafocallengthof10cm Whereistheimage Verifyyouranswerbygraphicalconstructionoftheimage 2 Alensisknowntohaveafocallengthof30cminair Anobjectisplaced50cmtotheleftofthelens Locatetheimage P36 1 3 17 Keywordsandconcept 1 Magnification Transversemagnification Lateralmagnification isdefinedastheratioofimagesize y toobjectsize y Axialmagnification longitudinalmagnification isdefinedastheratioofashortlength ordepth intheimagemeasuredalongtheaxis totheconjugatelengthintheobject Intheair itisequaltothesquareofthetransversemagnification Angularmagnification magnifyingpower Thetotalmagnificationofacombinationoflensesistheproductofthemagnificationoftheindividuallenses 18 Keywordsandconcept 2 Nodalpointsarewherenorefractionoccurs Whenevertherefractiveindicesoneithersideofthelensarethesame thenodalpointscoincidewiththeprincipalpoints Iftherefractiveindicesonthetwosidesofthelensaredifferent theNpointswouldmoveawayfromtheprincipalplanes towardthesideofhigherindex 19 Homework 1 Theobjectisatransparentcube 4mmacross placed60cminfrontofalensof20cmfocallength Calculatethetransverseandaxialmagnificationanddescribewhattheimagelookslike P36 4 6 20 Keywordsandconcept 1 Planemirrorwrong readingIfamirrorisrotatedthroughagivenangle abeamreflectedbythemirrorwillberotatedthroughtwicethatangle 21 Keywordsandconcept 2 Prismsaredividedintotwogroups reflectingprismsanddispersingprisms 3 Somereflectingprisms right angleprisms roof Porro prisms Dove erecting prisms pentagonalprisms 22 Keywordsandconcept 4 Dispersingprisms Elementsofaprism Apex Apexangle Angleofdeviation Base Prismequation 23 Keywordsandconcept 5 DispersionGenerally theindexdecreasesasthewavelengthincreases TheeffectisChromaticdispersion 24 Keywordsandconcept 6 Opticalmaterial glass crystal plastic Crownglass lowdispersion Flintglass highdispersion 25 Keywordsandconcept 7 MaterialcharacteristicsFraunhoferlines blueF yellowD redC MeandispersionisnumericaldifferencebetweenthetworefractiveindicesnFandnC DispersivepowerAbbe snumber 26 Keywordsandconcept 1 Stopsareeitherthefinitesizeofthelensesoradditionaldiaphragmsinopticalsystemwhichlimitthebundleoflightpassingthroughincrosssection 27 Keywordsandconcept 2 Theoryofstops3 Anaperturestopisanopening usuallycircular inanotherwiseopaquescreen 28 Keywordsandconcept 4 TheApertureratioofthesystemistheratioD f It sreciprocalisf stopnumber 5 Pupils entrancepupil exitpupil 29 Keywordsandconcept 6 Afieldstop incontrasttoanaperturestop limitstheangularfield orfieldofview 7 Windows entrancewindow exitwindow 8 Telecentricontheobject image side 30 Homework 1 Astop8mmindiameterisplacedhalfwaybetweenanextendedobjectandalarge diameterlensof9cmfocallength Thelensprojectsanimageoftheobjectontoascreen14cmaway Whatisthediameteroftheexitpupil 31 2 Twolenses alensof12 5cmfocallengthandaminuslensofunknownpower aremountedcoaxiallyand8cmapart Thesystemisafocal thatislightenteringthesystemparallelatonesideemergesparallelattheother Ifastop15mmindiameterisplacedhalfwaybetweenthelenses 1 Whereistheentrancepupil 2 Whereistheexitpupil 3 Whataretheirdiameters Homework 32 Keywordsandconcept 1 AberrationsMonochromaticaberrations Sphericalaberration coma astigmatism curvatureoffield distortion Chromaticaberrations 33 Keywordsandconcept 2 Monochromaticaberrationscanbefurtherdividedintotwogroupsdependingonwhetherornottheycausetheimageblur Imagebluroccursinsphericalaberration comaandobliqueastigmatism 34 Keywordsandconcept Curvatureoffieldanddistortioncausedislocationswithintheimagebutnoblur 35 3 Waveaberration Thedegreeofdeparturefromtruesphericity thatis thedistancebetweentheidealreferencesphereandtheactual distortedwavefront measuredalongtheradiusofthereferencesphere Keywordsandconcept 36 Homework Answerthefollowingquestions 1 Whatisanaberration Howdoesitcome 2 Howcanweclassifytheaberration 3 Whatiswaveaberration Whatrelationshipamongwaveaberrationandotheraberrations 37 Homework Readingthecomplementaryinformationandfillinthefollowingform 38 HomeworkAnswer 1 Whatisanaberration Howdoesitcome Anaberrationisthedifferencebetweentherealimageandtheidealimage Inparaxial raytracing whichwediscussedearlierinconjunctionwithsinglesurfacesandthinlenses wehadassumedthattheangleswhichtherayssubtendwiththeopticaxisare 39 small Ifthisisso thesinesoftheseanglescanbesetequaltotheanglesthemselves inradians Infact theanglesarelarger andifweuseexactraytracing thiscannolongerbedone Thesineofananglemustthenberepresentedbyaseriesexpansion Sothedifferenceoccurs HomeworkAnswer 40 HomeworkAnswer 2 Howcanweclassifytheaberration 41 HomeworkAnswer 3 Whatiswaveaberration Whatrelationshipamongwaveaberrationandotheraberrations Thedegreeofdeparturefromtruesphericity thatis thedistancebetweentheidealreferencesphereandtheactual distortedwavefront measuredalongtheradiusofthereferencesphere 42 Generallyspeaking thelargergeometricalaberrationis thelargerwaveaberrationis Sphericalaberration coma andastigmatismallhavecharacteristicwavefrontdistortions Incurvatureoffieldanddistortion thewavefrontnormalscometogetherbutatthewrongpoint HomeworkAnswer 43 Homeworkanswer Fillinthefollowingform 44 Apersonwantstolookattheimageofhisorherowneyes withoutaccommodation usingaconcavemirrorof60cmradiusofcurvature Howfarmustthemirrorbefromtheeyeifthepersonhas1 Normalvision 2 4dioptermyopia withoutcorrection 3 4diopterhyperopia withoutcorrection Homework 45 Keywordsandconcept 1 Crosssectionofthehumaneye 46 Keywordsandconcept 2 Reducedeyeandschematiceye3 Accommodationisaccomplishedbyachangedofpowerofthelens resultingfromachangeofshape 47 Keywordsandconcept 4 Normalvision5 AnomaliesMyopia nearsightedness Hyperopia hypermatropia farsightedness 48 Homework Apersonwantstolookattheimageofhisorherowneyes withoutaccommodation usingaconcavemirrorof60cmradiusofcurvature Howfarmustthemirrorbefromtheeyeifthepersonhas1 Normalvision 2 4dioptermyopia withoutcorrection 3 4diopterhyperopia withoutcorrection P140 1 2 49 Keywordsandconcept 1 Microscope Amicroscopeisaninstrumentforviewingobjectsthatareverysmall Itisatwolenssystem anobjectiveofshortfocallengthandaneyepiece Thedistancebetweentheright handfocusoftheobjectiveandtheleft handfocusoftheeyepieceiscalledtheopticaltubelength 50 Keywordsandconcept 2 Thestructureofamicroscope 51 Keywordsandconcept 3 Numericalaperture NA4 Thedistanceofmostdistinctvision 25cminfrontoftheeye 52 Keywordsandconcept 5 TelescopeKepler stelescopecontainstwoconverginglenses anobjectiveoflongfocallengthandaneyepieceofshortfocallength Thelensesarespacedsothatthesecondfocusofthefirstlenscoincideswiththefirstfocusofthesecondlens 53 Keywordsandconcept Galileo stelescopecontainstwolenses theobjectiveispositiveandtheeyepieceisnegative Stillthetwofocalpointscoincide 54 Theimageisseenatinfinity withaccommodation theimageisseenatthedistanceofmostdistinctvision Instrumentmyopiaisaphenomenonthatapersoninvoluntarilyaccommodateswhenheorshelooksintoanopticalinstrument Keywordsandconcept 55 Homework Discussion Whatdifferencesbetweenthefollowingsituations 1 amicroscopeisusedforprojection 2 themicroscopeisusedforvisualobservation P140 3 6 56 Supplementarymaterials 1 Digitalcamera 工作原理颜色的形成分色棱镜覆盖转轮指标像素数颜色深度 57 Supplementarymaterials BAYER编码 三色编码 58 Homework Classificationofcameralenses 1 Tessarcameralens mostwidelyused 2 Telephotolens3 Wide anglelens fisheyelens skylens4 AzoomlensP140 5 7 59 Briefhistoryoflaser ThewordLASERisanacronymforlightamplificationbystimulatedemissionofradiation In1916 Einsteinpredictedthattheexistenceofequilibriumbetweenmatterandelectromagneticradiationrequiredthatbesidesemissionandabsorptiontheremustbeathirdprocess nowcalledstimulatedemission 60 Thispredictionattractedlittleattentionuntil1954 whenTownesandcoworkersdevelopedamicrowaveamplifier Maser In1958 SchawlowandTownesshowedthatthemaserprinciplecouldbeextendedintothevisibleregion In1960 Maimanbuiltthefirstlaserusingrubyastheactivemedium Briefhistoryoflaser 61 Comparedtoradiationfromothersources laserradiationstandsoutinseveralways Ithasaparticularbeamshapeanddivergence Itishighlycoherent both