1、分類號鯉曼Lj二盟㈣UDC，密級公開～編號中國工程物理研究院學位論文高功率激光柬中高頻位相畸變特性的研究劉紅婕指導教師姓名景蜂(劇研究員)(中國工程物理研究院四川綿陽)申請學位級別碩士專業(yè)名稱光學工程論文提交日期2005年5月論文答辯日期2005年5月學位授予單位和日期史國工程物理研究院答辯委員會主席楊經鐲(教授)評閱人宋影松(研究員)2005年5月日羅斌(教授)高功率激光柬中高頻位相畸變特性的研究AbstractItiswellkno

2、wnthroughmanyfinishedphysicsexperimentsthatthecharacteristicoffocalspotisoneofthemostcrucialfactorswhichdeterminewhetherignitioncailrealizeornotPropertiesoffocalspotaremainlydeterminedbythequalityofthebeambeforefocusedIn

3、brief，themainoffocalspotliesonthelowfrequencycomponentsofwavefrontwhilethetailofitliesonthemiddle—highfrequencycomponentsofwavefrontManyresearchesaboutthelowfrequencycomponentsofwavefronthavecometoveryusefulconclusions，h

4、owever，forthemiddle—hi曲components，relativelylessworkhasbeendoneandnousefulresultshavebeenderivedaboutitsnonlinearpropagationoritsrelationwiththetailofthefocalspotbecauseofitscomplextransmissionThemiddlehighfrequencycompo

5、nentsofwavefrontinhi曲powerlasersystemmainlycomefromhundredsofopticsbecauseevenextremelysmallfiuctuationsonthesurfaceofoptiCSmaybecomenegligiblebyhundredsofadditionandnonlineartransmissionTheunwantedresultsfromitincludepi

6、nholeclosureandnonlinearsmall—scaleselffocusingwhichoriginatefromhigh—intensitytailofthefocalspotandnonlineartransmissionofthemiddle—hi曲frequencyunderhighintensitySoitisveryusefu／tostudythetransmissionofthemiddlehi曲frequ

7、encyanditsimpactonthetailofthefocalspotThecontentsaremainlydividedintofivesectionsasfollows：(1)DividingthespatialfrequencyofthephaseerrorsintoseveraldistrictsandmakingsurethedistricttostudyFirst，theB—Ttheoryitsassumption

8、sandanalysisofphaseerror’spropagationareintroducedThen，basingonthenonlinearpropagationofdifferentspatialfrequencyandtherequirementsofICFforthemainfocalspot，wedividethespatialfrequencycomponentsofphaseerrorsintoseveraldis

9、trictsfortheSG一17IsystemandmakesaretheemphasistOstudy(2)StudyingthetransmissionpropertiesofthemiddlehighfrequencycomponentsofphaseerroronthebasisofB—TtheoryWefirststudythetransmissionpropertiesofalocalphaseerroranddrawac

10、onclusionthatnoneofthephasecrrorsundergoapparentnonlinearincreaseexceptforthosewhosemainspatialfrequencycomponentsarcinthehi曲一gaindistrictThen，usingnumericalsimulation，westudytheimpactsofphaseerroronthenearfieldofthebeam

11、inpracticeandanalyzetherelationbetweenthe△BandthenearfieldcontrastFinallyweanalyzetheimpactsofpinholesanddifferentresourcesofphaseerroronthenearfieldmodulation(3)Impactsofmiddlevhi曲frequencycomponentsofphaseerroronthetai