简介:Studieshavebeencarriedouttotesttheassumptionthattheprimaryphotoreceptorsfortheradioprotectiveactionof633nmlaserradiationarethecytochrome-c-oxidases.Todothis,thedevicewascreatedforradiationprotectionofbiologicalobjectsbasedonlasermodulewithawavelengthof532nm.Experimentsconductedonmurinefibroblastcellsshowedthattheradioprotectioneffectoflaserirradiationwasobservedinthedoseintervalabout0.4-0.85mJ/cm2.Maximumradioprotectioneffectisobservedatlaserradiationenergydensity~0.56mJ/cm2.ThedeterminationofthecellsurvivalwiththeautomaticcounterСТ20aftertheactionoftheionizingandcombinedirradiationshowedthatradioprotectiveactionofthelaserradiationwiththewavelengthof533nm,aswellastheradiationwiththewavelengthof633nm,istransferredbythemechanismofthe“bystandereffect”.Inaddition,itwasfoundthatradioprotectioneffectoflaserirradiationobservedonthecriterionofnumberofsurvivingsinglecells,comparedwithcellsexposedto?-radiationLaserirradiation,produceseffectiveradioprotectingactionalsoonthecriterionofgrowncellcolonies.Thevalueofthedosemodificationfactor(DMF)calculatedon50%cellsurvival(LD50)isequalto1.4.Theresultssuggestthatinthecaseofradioprotectiveactionofsmalldosesoflaserradiationwithawavelengthof633nm,aswellas532nmprimaryphotoreceptorsisthecytochrome-c-oxidases.
简介:实现了X型腔全固态端面泵浦Cr:LiSAF激光器的高效率输出和宽谱调谐。斜效率最高为33.3%,在吸收泵浦功率为650mW时,输出功率最高达160mW。在谐振腔内插入双折射滤光片(BF)调谐,调谐范围达787.952nm。测量了激光器的光谱、光束质量等,分析了激光器效率和调谐范围的限制因素。研究表明,X型腔全固态端面泵浦的Cr:LiSAF激光器可以实现高效的近红外宽谱调谐输出。
简介:Wepresentanovelandsimplemethodtoobtainanultrawidefreespectralrange(FSR)siliconringresonatortogetherwithatuningrangecoveringtheentirespectrumfrom1500to1600nm.AringresonatorwithalargeFSRtogetherwithahighQfactor,hightuningefficiency,andlowfabricationcostandcomplexityisdesiredformanyapplications.Inthispaper,weintroduceanovelwaytomakesucharingresonator,whichtakesadvantageofthewell-knownresonance-splittingphenomenon.ItisasingleringresonatorwithanFSRofmorethan150nmaround1550nmandwhichhasaneasythermo-optictunabilitythatcanproduceatuningrangearound90nmorevenmore.Moreover,thedeviceissimpletoimplementandcanbefabricatedinstandardcomplementarymetal-oxidesemiconductortechnologywithoutrequiringanykindofcomplicatedprocessingorextramaterials.Thepotentialapplicationsincludesinglemodelasercavities,wavelengthdivisionmultiplexingfilters,(de)multiplexers,opticalsensors,andintegratedreflectors.
简介:TN2412006064910液体物质中的空化现象实验研究=Experimentalresearchoncavitationbubbleinwater[刊,中]/赵瑞(南京理工大学应用物理系.江苏,南京(210094)),徐荣青…//光电子·激光.—2006.17(5).—629—633采用自行研制的光偏转测试系统对强激光诱导液体物质的空化现象进行了实验研究,实验得到了激光等离子体冲击波传播规律和空泡的动力学特性。结果表明,激光等离子体冲击波在其传播过程中迅速衰减为声波;激光空泡的最大泡径随脉动次数增加依次减小,而收缩的最小泡径则由腔内含气量决定。图7参11(严寒)
简介:P225.22005010205基于CPLD的脉冲激光测距飞行时间测量=MeasurementofflighttimeforpulsedlaserrangingbasedonCPLD[刊,中]/杨成伟(清华大学电子工程系.北京(100084)).霍玉晶…∥激光与红外.-2004.34(2).-106-108研制了基于CPLD的脉冲激光测距飞行时间测量系统。CPLD的使用提高了激光测距仪的精度,并且可灵活修改设计,使同一硬件系统可用于不同类型的脉冲激光测距仪的飞行时间测量。此系统结构简单,体积小,可靠性高,非常适合高性能手持式脉冲激光测距仪。图2参5(杨妹清)
简介:Transversemodecharacteristicsofalaserarerelatedtoavarietyofinterestingapplications.Anon-demandmodesolidlaserinthe1064nmbandwasproposedpreviously.Inthispaper,weprovideafiberlaserforon-demandmodesinthe1550nmbandtoprescribethepureandhigh-qualityemissionofahigher-ordertransverselasermode,basedonasimpleconstructionwithonespatiallightmodulator(SLM)andasingle-modeerbium-dopedfiber(SM-EDF).TheSLMisdesignatedtogeneratethedesiredhigher-ordermodeandseparatethehigher-ordermodeandthefundamentalmode.Thefundamentalmodeoscillatesinthefiberringlaser,andthereforetheSM-EDFcanbepumpedwithasingle-mode980nmlaser,nomatterwhathigher-ordermodeisprescribed.Inthisproof-of-principleexperiment,high-qualityhigher-ordermodesareobservedfromLP01toLP105.Stableemissionandreal-timeswitchingbetweenmodescanbeeasilyrealizedbyalteringthephaseontheSLM.Inaddition,thepropagationoftheLP01,LP11,LP21,andLP02modesfromthefiberlaserisalsodemonstratedinafour-modefew-modefiber.
简介:Anall-solid-statesingle-frequency1064nmlaserwitha100μspulsewidth,500Hzrepetitionrateand700mJsinglepulseenergyisdesignedusingseedinjectionandathree-stagemasteroscillatorpoweramplifier(MOPA)construction.Usingthisasabasis,researchonlong-pulselaserfrequencydoublingiscarriedout.Bydesigningandoptimizingthelithiumtriborate(LBO)crystal,thetheoreticallycalculatedmaximumconversionefficiencyηmaxreaches68%atM2=1,whileηminis33%atM2=3.Generationof212mJpulsesofgreenlightwitharepetitionrateashighas500Hzisobtainedfromafundamentalenergyof700mJ.Theexperimentalconversionefficiencyreaches31%andthepowerstabilityisbetterthan±1%.