高功率激光器中頻波段傳輸特性研究.pdf

1、獨(dú)創(chuàng)性聲明本人聲明所呈交的學(xué)位論文是本人在導(dǎo)師指導(dǎo)下進(jìn)行的研究工作及取得的研究成果。據(jù)我所知，除了文中特別加以標(biāo)注和致謝的地方外，論文中不包含其他人已經(jīng)發(fā)表或撰寫(xiě)過(guò)的研究成果，也不包含為獲得中國(guó)工程物理研究院或其他教育機(jī)構(gòu)的學(xué)位或證書(shū)使用過(guò)的材料。與我一同工作的同志對(duì)本研究所做的任何貢獻(xiàn)均已在論文中作了明確的說(shuō)明并表示謝意。學(xué)位論文作者簽名：參＼蟛簽字日期：列3年6月7日學(xué)位論文版權(quán)使用授權(quán)書(shū)本學(xué)位論文作者完全了解并接受中國(guó)工程物理研究

2、院研究生部有關(guān)保存、使用學(xué)位論文的規(guī)定，允許論文被查閱、借閱和送交國(guó)家有關(guān)部門(mén)或機(jī)構(gòu)，同時(shí)授權(quán)中國(guó)工程物理研究院研究生部可以將學(xué)位論文全部或部分內(nèi)容編入有關(guān)數(shù)據(jù)庫(kù)進(jìn)行檢索，可以影印、縮印或掃描等復(fù)制手段保存、匯編學(xué)位論文。學(xué)位論文作者簽名：吾＼蟛簽字日期：馴弓年6月7日導(dǎo)師簽名：乒伶導(dǎo)師簽名：咖／／≥簽字日期：ⅫB年舌月7日高功率激光器中頻波段傳輸特性研究AbstractICF(InertialConfinementFusion)nee

3、dshiglltemperaturesanddensitiesreliedonhighpowersolidstatelaserdrivertoachievethefusionreactionconditions，soitrequiresoutputgoodbeamqualityInordertoensurehighharmonicconvemionefficiencyandgettingthroughthepin—llolethebea

4、mmusthavegoodnearfielddistributionuniformityandwavefontInthesimilarNIFdevice，Iargeapertureelectroopticalswitchl①Pcrystalactingasakeycomponentofthefourpassamplifierduetoitsmaterialpropertiesandprocessingmethodswillintrodu

5、cealotofmiddleandhi曲frequencyinformationCombinedwithwavecontrolmethodsinthedeviceitcanbeanalyzedthatsomeofitsfrequencycangetthroughthepinholeandcan’tbecorrectedbydeformablemirror111emiddlefrequencywavefronthasagreatimpac

6、tonnearfieldintensityuniformityandfarfieldfocusingabilitythuslimitsthecapabilitiesofthesystemloadInordertoanalyzetheeffectsofthemiddlefrequencywavefront，thepapercarriesoutthefollowingjobs：Firsttostudythecurvedmodulationi

7、nthenearfielddatacolleeredbyCCDintheexperimentsfilteringanalysisonthetypicalNd：glassandKDPcrystalisdonetofindoutthatthereareresidualperturbationwhichhaveaperiodof20mmontheKDPcrystalAccordingtothewavefrontspacebanddivisio

8、nandlaserdevicesystemcharacteristicscomparethedataofthe33mmhighpassfilteringontheopticalcomponentswithNIFstandardcurveandhaveageneraliudgmentonthemodulationcardedbyKDPcrystalcontributingtothefmaloutputofthesystemSecondac

9、alculationmodelwhichisbasedonFFTtheoryanopticswavefrontdataofSGIIisestablishedand，getdifferentnearfielddistribufionsinthreecases：withmiddleandhi小frequenciesintroducedbyKDPcrystal；withoutl①Pcrystal；withtheincreasedmiddlea

10、ndhighfrequenciesmodulationItcanbefoundthatbecausetheKDPcrystalhasamuchhigherpowerspectraldensitytheotheropticalelementsinmiddlebandfrequency，asimilarperiodicdistributionofintensityinnearfieldcanbefoundandthecontrastofth

11、enearfieldwillbesignificantlyincreasedandtheuniformitywillgetworsewhentheperturbationincreases111irdintroducethe‘spatialcoordinatetransformationmethod’whichisusuallyusedinshortwaveandshortfocallengthsystemtocalculatefarf

12、ieldfocalspotunderthelargeapertureandlowsamplingratecaseSimulatethefarfieldfocalspotsindifferentspatialfiltersindifferentcasesandgetthemiddle—frequencyperturbationwhichcangetthroughthepinholeimpactonthesizeofthefocalspot

13、Atlast。intheparaxialapproximation，waveequationinnonlinearmediacanbederivedbasedonMaxwell’sequationsCalculatethefastestgrowthfrequenciesindifferentpropagationintervalaccordingtoBTtheoryEstablishthephasedefectsmathematical

14、expressionandanalyzeitspropagationinnonlinearmedia，calculatetheamplitudegrowthofdifferentdefects’size，thusabasicunderstandingonlocalizedwavefrontdefectsinICFlaserdevicecanbegotKeywords：highpowerlaserdeviceKDPcrystal，spat