激光技术
激光技術
격광기술
LASER TECHNOLOGY
2013年
5期
636-641
,共6页
唐建%左都罗%杨晨光%程祖海
唐建%左都囉%楊晨光%程祖海
당건%좌도라%양신광%정조해
激光技术%光谱学%激光诱导等离子体%时间和空间分辨光谱%电子温度和电子密度
激光技術%光譜學%激光誘導等離子體%時間和空間分辨光譜%電子溫度和電子密度
격광기술%광보학%격광유도등리자체%시간화공간분변광보%전자온도화전자밀도
laser technique%spectroscopy%laser-induced plasma%spatio-temporal evolution spectroscopy%electron temperature and electron density
为了了解激光诱导等离子体的演化过程,得到等离子体的相关参量,采用横向激励大气压CO2激光器在抛物反射面中聚焦击穿空气形成等离子体,利用成像光谱仪和增强型CCD探测器对激光诱导等离子体进行了时间和空间分辨的实验分析,取得了激光诱导空气等离子体的时间演化和空间分辨光谱。分别利用氧原子的线状谱和连续谱的比值及谱线半峰全宽计算得到电子温度达到了4×104 K,电子密度在1018 cm-3量级。结果表明,相比于低能量的激光诱导等离子体的辐射光谱,高能量激光诱导的等离子体则向外辐射出很强的连续光谱,同时,等离子体以激光支持爆轰波的形式快速向外膨胀,由于外围等离子体对激光能量的屏蔽作用,等离子体出现了空间分离的现象。该研究结果对理解等离子体和高能量脉冲激光的相互作用过程是有帮助的。
為瞭瞭解激光誘導等離子體的縯化過程,得到等離子體的相關參量,採用橫嚮激勵大氣壓CO2激光器在拋物反射麵中聚焦擊穿空氣形成等離子體,利用成像光譜儀和增彊型CCD探測器對激光誘導等離子體進行瞭時間和空間分辨的實驗分析,取得瞭激光誘導空氣等離子體的時間縯化和空間分辨光譜。分彆利用氧原子的線狀譜和連續譜的比值及譜線半峰全寬計算得到電子溫度達到瞭4×104 K,電子密度在1018 cm-3量級。結果錶明,相比于低能量的激光誘導等離子體的輻射光譜,高能量激光誘導的等離子體則嚮外輻射齣很彊的連續光譜,同時,等離子體以激光支持爆轟波的形式快速嚮外膨脹,由于外圍等離子體對激光能量的屏蔽作用,等離子體齣現瞭空間分離的現象。該研究結果對理解等離子體和高能量脈遲激光的相互作用過程是有幫助的。
위료료해격광유도등리자체적연화과정,득도등리자체적상관삼량,채용횡향격려대기압CO2격광기재포물반사면중취초격천공기형성등리자체,이용성상광보의화증강형CCD탐측기대격광유도등리자체진행료시간화공간분변적실험분석,취득료격광유도공기등리자체적시간연화화공간분변광보。분별이용양원자적선상보화련속보적비치급보선반봉전관계산득도전자온도체도료4×104 K,전자밀도재1018 cm-3량급。결과표명,상비우저능량적격광유도등리자체적복사광보,고능량격광유도적등리자체칙향외복사출흔강적련속광보,동시,등리자체이격광지지폭굉파적형식쾌속향외팽창,유우외위등리자체대격광능량적병폐작용,등리자체출현료공간분리적현상。해연구결과대리해등리자체화고능량맥충격광적상호작용과정시유방조적。
In order to study the evolution of laser-induced plasma and obtain the properties of plasma , transversely excited atmospheric CO 2 laser was focused by a parabolic reflector to generate air breakdown plasma .Based on the imaging spectrometer system and intensified CCD detector , time-space resolution of laser-induced air plasma were investigated and the time evolution spectra and the space resolution spectra of plasma were obtained .Electron temperature of about 4 ×104 K and electron density of 1018 cm-3 were calculated respectively by using the ratio of oxygen line spectrum and continuous spectrum and full width at half maximum of spectral line .The results show high-energy laser-induced plasma spectra radiate the intense continuous spectra outward , comparing with low-energy laser-induced plasma spectra .At the same time , laser-induced air plasma expands outward rapidly with the way of the laser-supported detonation wave .Due to the shielding effect of laser power , laser-induced air plasma shows the behavior of spatial separation .The results are useful for understanding the interaction between plasma and high-energy laser .