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1、ANINTRODUCTIONTOX-RAY班级：09物理学姓名：刘磊学号：20091101181.HISTORYXrayshaveacenturyofhistoryofmedicalandtechnologicalapplications.Opticshavecometoplayanimportantroleinmanycapacities.OneofRoentgen"searliestobservations,shortlyafterhisdiscoveryofxraysin1895,wasthatwhiletherayswereeasilyabsorbedbys
2、omematerials,theydidnotstroiiglyrefract.Standardoptical1enses,whichrequireweakabsorptionandstrongrefraction，werethereforenotusefulformanipulatingtherays.Newtechniqueswerequicklydeveloped.In1914,vanLauewasawardedtheNobelPrizefordemonstratingthediffractionofxraysbycrystals.By1929,totalre
3、flectionatgrazingincidencehadbeenusedtodeflectxrays.Theavailableopticsforxraysstillcanbeclassifiedbythosethreephenomena:refraction,diffraction,andtotalreflection.Surprisingly,giventhatthephysicsgoverningtheseopticshasbeenwellknownfornearlyacentury,therehasbeenarecentdramaticincreaseint
4、heavailability,variety,andperformanceofx-rayopticsforawiderangeofapplicatioiis.Anincreasinginterestinx-rayastronomywasoneofthemajorforcesforthedevelopmentofx-rayopticsinthelatterhalfofthelastcentury.Mirrorsystemssimilartothosedevelopedforastronomyalsoprovedusefulforsynchrotronbeamlines
5、.Justasx~raytubeswereanaccidentaloffshootofcathoderayresearch,synchrotronx~raysourceswereoriginal1yaparasiteofparticlephysics.Thesubsequentdevelopmentofsynchrotronswithincreasingbrightnessandnumbersofbeamlineshavecreatedwholenewarraysofx-raytoolsandaconsequentdemandforanincreasingarray
6、ofoptics.Therapiddevelopmentofx~rayopticshasalsobeensymbioticwiththedevelopmentofdetectorsandofcompactsources.Detectorsdevelopedforparticlephysics,medicine,andcrystallographyhavefoundapplicationsacrossfields.Similarly,theincreasingcapabilityofx-raysystemshasstimulatedthedevelopmentofne
7、wsciencewithevergrowingrequirementsforintensity,coherence,andspatialandenergyresolution.X-raydiffractionandfluorescencewereearlytoolsoftherapiddevelopmentofmaterialsscienceafterWorldWarII,buthavebeengreatlyadvancedtomeetthedemandsoftheshrinkingfeaturesizesandalloweddefectlevelsinsemi
