MIT-光学教程wk8b (3)

《MIT-光学教程wk8b (3)》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、䗣䬰੠៤ڣ˄㄀ϔ䚼ߚ˅LensesandImaging(PartI)噝៤ڣⱘᖙ✊ᗻ˖ᚴ᳈ᮃॳ⧚ˉ᮴䰤䖰ᑇ㸠ܝ੠⧗䴶ܝᴳ•Whyisimagingnecessary:Huygen’sprinciple噝⧗䴶ᡬᇘ˄١䕈䖥Ԑ˅–Spherical¶llelraybundles,pointsatinfinity噝ܝ⛺ᑺ੠៤ڣᴵӊ噝޴ԩܝᄺⶽ䰉݀ᓣ•Refractionatsphericalsurfaces(paraxialapproximation)噝㭘䗣䬰•Opticalpowerandimagingcondition噝ℷ䋳ܝ⛺ᑺ

2、ⱘ㸼䴶•Matrixformulationofgeometricaloptics噝ᅲڣ੠㰮ڣ•Thethinlens•Surfacesofpositive/negativepower•RealandvirtualimagesMIT2.71/2.71009/15/04wk2-b-1Parabloidmirror:perfectᡯ⠽䴶䬰:⧚ᛇ㘮⛺focusing(՟བ(e.g.satellitedish)ि᯳ᡯ⠽䴶ডᇘ䬰)xs(x)f:⛺䎱z2xs()x=f4fMIT2.71/2.71009/15/04wk2-b-2Lens:maini

3、nstrumentforimage䗣䬰˖៤ڣⱘЏ㽕Ꮉ݋formationぎ⇨ぎ⇨air⦏⩗opticalܝ䕈axis⚍ڣ⚍⑤˄⠽˅PointsourcePointimage(object)ᣝ✻ᮃ⍙ᇨᅮᕟˈᔃ᳆㸼䴶Փܝᴳথ⫳أᡬˈأᡬᑺϢᅗӀ⾏¯ܝ䕈āⱘ䎱⾏៤ℷ↨ˈথᬷⱘ⊶ࠡ೼Thecurvedsurfacemakestheraysbendproportionallytotheirdistancefromthe“opticalaxis”,accordingtoSnell’slaw.Therefore,thedivergentߌⱘে᠟˄

4、䕧ߎ˅ᮍথ⫳Ӯ㘮DŽwavefrontbecomesconvergentattheright-hand(output)side.MIT2.71/2.71009/15/04wk2-b-3WhyarefocusinginstrumentsЎҔМӮ㘮㋏㒳ᰃᖙ䳔ⱘ˛necessary?•Raybundles:sphericalwavesandplanewavesܝᴳ˖⧗䴶⊶੠ᑇ䴶⊶•Pointsourcesandpointimages⚍⑤੠⚍ڣ•Huygensprincipleandwhywecanseearoundusᚴ᳈ᮃॳ⧚ǃЎҔМ៥Ӏ

5、㛑ⳟࠄ਼ೈⱘϔߛ•Theroleofclassicalimagingsystems㒣݌៤ڣ㋏㒳ⱘ԰⫼MIT2.71/2.71009/15/04wk2-b-4Ӵ᪁ܝ㒓ᴳRaybundlespoint⧗䴶⊶spherical⚍⑤source˄থᬷ˅wave(diverging)wave-front⊶ࠡ^ܝᴳrayspointsourcewave-front⊶ࠡ^ܝᴳraysvery-veryᕜ䖰ᕜ䖰ⱘfaraway⚍⑤……planeÑᑇ䴶⊶waveMIT2.71/2.71009/15/04wk2-b-5ᚴ᳈ᮃॳ⧚Huygensprinc

6、iple⊶ࠡϞⱘ↣ϔϾ⚍ܙᔧ⃵⚍ܝ⑤ˈথᇘ⧗䴶⊶㒣䖛ⷁⱘӴ᪁䎱⾏ৢⱘ⊶ࠡᰃ᠔᳝䖭ѯ⃵⧗䴶⊶঴ࡴⱘ㒧ᵰܝ⊶ࠡMIT2.71/2.71009/15/04wk2-b-6WhyarefocusinginstrumentsЎҔМӮ㘮㋏㒳ᰃᖙ䳔ⱘ˛necessary?ܹᇘܝincidentlight...isscatteredby㹿⠽ԧᬷᇘtheobjectobject⠽ԧMIT2.71/2.71009/15/04wk2-b-7WhyarefocusinginstrumentsЎҔМӮ㘮㋏㒳ᰃᖙ䳔ⱘ˛necessary?ܹᇘܝincidentl

7、ight...isscatteredby㹿⠽ԧᬷᇘtheobjectΩneedopticsto“undo”䳔㽕ܝᄺ㋏㒳ᴹ¯⸈theeffectsofscattering,ണāᬷᇘᬜᑨˈ՟བ㘮⛺ܝᴳobject⠽ԧi.e.focusthelightimageڣMIT2.71/2.71009/15/04wk2-b-8⧚ᛇ䗣䬰Ideallensぎ⇨ぎ⇨air⦏⩗ܝ䕈⚍⑤ڣPointsources⚍⑤˄⠽˅Pointimages(object)Eachpointsourcefromtheobjectplanefocusesontoapoin

8、tobjectplaneᴹ㞾⠽ᑇ䴶Ϟⱘ↣ϔϾ⚍⑤೼ڣᑇ䴶Ϟ㘮⛺ЎϔϾ⚍ڣDŽimageattheimageplane;imageplaneNOTEtheimageinversion⊼ᛣ˖೒ڣצ㕂MIT2.71/2.71009/15/04