1.3JXeCl激光器的注入锁定

报道了1.36J单脉冲能量的水传输线充电、轨道开关主放电XeCI激光器非稳腔注入锁定。注入锁定激光输出功率18MW、线宽8.9×10~(-3)A、空间发散角0.2mrad。讨论了XeCI激光器注入锁定的一些参量以及放电同步特性。     

高功率TEA CO_2激光器非稳腔实验研究

为了提高光束质量、压缩光束发散角,利用现有高功率稳定腔TEA CO2激光器进行了非稳谐振腔的技术改造及激光输出试验,非稳谐振腔采用正分支虚共焦型非稳腔方案。为充分研究谐振腔结构参数及激光振荡模体积对输出能量和光束发散角的影响,共设计加工了包含4种放大率、5种模体积的20组非稳腔腔镜组合。在其它参数都相同的试验条件下,进行了非稳腔镜的单脉冲输出对比试验,得到的最大输出能量为14 J,是原平凹稳定腔的70%,而光束发散角只是原平凹稳定腔的1/4。     

内腔式虚共焦非稳腔光参量振荡器激光器的光束质量检测

基于内腔式虚共焦非稳腔的理论优化结果和理论远场发散角4.05 mrad,对光参量振荡器（OPO）激光器的光束质量进行了检测实验,输出激光能量可达70.6 mJ/脉冲,远场发散角最小达5 mrad;分析了影响OPO光束质量的可能因素,验证了经过优化设计的OPO激光器能够获得高光束质量的1.57 m激光。     

宽工作温度全固态人眼安全光参量振荡器

采用折叠棱镜腔电光调Q半导体泵浦板条Nd∶ YAG激光器作为泵浦源,内腔泵浦Ⅱ类非临界相位匹配KTP光参量振荡器实现1.57 μm人眼安全激光输出,经测试,在30～55℃宽工作温度条件下,激光器工作频率20 Hz时,单脉冲能量58.2mJ,脉冲宽度7.56 ns,光束发散角约为2 mrad,连续工作1 min,能量稳定性(PTP)优于6.438％,光轴指向稳定性优于0.1mrad,具备较强环境适应性,目前已实现工程化运用.     

适用于水下同步照明的灯泵浦绿光激光器研制

研制了脉冲宽度大、单脉冲能量大的绿光激光器,其中脉冲重复频率与高速相机帧频同步,且光纤耦合输出.激光器采用平凸非稳腔结构,灯泵浦Nd∶YAG晶体,KTP晶体内腔倍频,被动调Q方式,实现了最大重复频率为300Hz、脉冲宽度为70μs、平均功率为38W、单脉冲能量为126.7mJ、光束发散角为3.5mrad的532nm激光输出.将该激光耦合到芯径为800μm的光纤中进行水下实验,耦合效率达到92%.     

角锥棱镜腔激光二极管抽运被动调Q激光器

为了提高传导冷却条件下激光二极管(LD)侧向抽运被动调Q激光器的光束质量和输出稳定性,采用了两组半圆柱面激光二极管阵列侧向交错抽运两根串接的激光棒,实现了均匀抽运和散热。通过实验分析了横模结构对被动调Q稳定性的影响,设计了角锥棱镜-高斯输出镜非稳腔,在显著提高器件光束质量的同时,明显改善了被动调Q的稳定性,并保证了谐振腔的机械稳定性。在此基础上研制了一台重复频率20 Hz、单脉冲能量64 mJ、脉冲宽度7 ns、稳定性优于±5%、光束发散角0.6 mrad、光-光效率9.1%,且光轴指向稳定的工程实用器件。     

采用液态金属传热的小型大功率全固态Nd∶YAG板条激光器

 为了满足小型光电系统对微小型大功率激光器的研制要求,通过液态金属传热设计,提高散热效率,使得激光器在小体积下实现高能量输出。采用复合板条工作物质集成谐振腔以及激光放大技术,在激光电源电流80 A、工作频率为5 Hz时,激光器在1064 nm输出单脉冲能量为160 mJ,脉宽为6 ns,发散角为3 mrad的激光。     

200 mJ半导体端面泵浦MOPA激光器研究

采用高功率激光二极管阵列(LDA)端面泵浦Nd:YAG激光棒方式, 结合凸凹非稳腔的设计，获得20 Hz运转条件下小束散角激光输出平均能量约为83 mJ。以该激光为振荡源，同样采用LDA端面泵浦Nd:YAG激光棒的方式进行能量放大，组成LDA端面泵浦振荡-放大(MOPA)激光器，最终获得重频频率20 Hz、平均能量＞200 mJ、发散角＜2.1 mrad、能量波动＜±2.5%的脉冲激光输出。该激光器光光转换效率约为14.6%，体积为175×91×49 mm3，质量＜1 kg，激光经8倍发射天线后发散角＜0.3 mrad。     

角隅全反镜谐振腔激光器的输出特性

 在高功率脉冲气体激光器中，用角隅反射镜作为全反镜，平行平面镜作为输出镜构成角隅全反镜谐振腔。对角隅腔激光器的输出特性和抗失调稳定性进行了研究，并与平凹腔和平平腔激光器进行了比较。实验结果表明：在角隅全反镜失调角为16 mrad时，角隅腔激光器的单脉冲输出能量下降9.2%，且近场输出光斑没有明显变化；而凹面全反镜失调角仅为0.4 mrad时，平凹腔激光器输出能量下降了9%，近场输出光斑严重变形。在输出镜正前方3.12 m处测量，当角隅镜偏转16.3 mrad时，激光器输出光斑与标准状态时的输出光斑重合；凹面全反镜失调角为0.4 mrad时，激光器输出光斑位移14 mm。经模式仪分析表明，角隅腔激光器近场光强分布均匀。     

1kHz窄脉宽高峰值功率MgO∶LN电光腔倒空Nd∶YAG激光器

报道了一种1kHz窄脉冲宽度、高峰值功率的电光腔倒空1 064nm全固态激光器.该激光器采用808nm脉冲LD侧面泵浦Nd:YAG晶体棒的双凹型折叠谐振腔结构和同步延迟MgO∶LN晶体横向加压式电光腔倒空技术,通过优化设计谐振腔结构,在脉冲重复频率200Hz时,获得了最大单脉冲能量46.7mJ、脉冲宽度4.06ns、峰值功率11.50MW的1 064nm脉冲激光稳定输出,脉冲宽度和能量的峰峰值不稳定度分别为±1.52%和±2.02%;在1kHz时,最大单脉冲能量达到18.3mJ,脉冲宽度5.02ns,峰值功率3.69MW,脉冲宽度和能量的峰峰值不稳定度分别为±2.75%和±3.52%,激光束因子为3.849和3.868,远场发散角为3.46mrad和3.55mrad,束腰直径为1 508.84μm和1 477.30μm.     

Long-pulse KrCl laser with a high discharge quality

The discharge quality and optimum pump parameters of a long-pulse high-pressure gas discharge excited KrCl laser are investigated. A three-electrode prepulse–mainpulse excitation circuit is employed as pump source. The discharge volume contains a gas mixture of HCl/Kr/Ne operated at a total pressure of up to 5 bar. For a plane–plane resonator, the divergence of both output laser beams is measured. A low beam divergence of less than 1 mrad is measured as a result of the very high discharge homogeneity. A maximum laser pulse duration of 150 ns (FWHM) is achieved for a pump duration of 270 ns (FWHM) and a power density of 340 kW cm^-3. Pumping the discharge under optimum conditions employing a stable resonator results in a maximum specific energy of 0.45 J/l with a laser pulse duration of 117 ns and an efficiency of 0.63% based on the deposited energy. PACS 42.55.Lt; 52.25.-b; 52.59.Ye     

Performance of a 80 W copper vapor laser with “alignment free” unstable CAT-EYE resonator and other configurations using intra-cavity apertures

Performance of a kinetically enhanced copper vapor laser (KE-CVL) with various stable/unstable “alignment free” CAT-EYE resonator configurations are presented here in this paper. The laser used in the experiment was a 45 mm bore (∼2 l discharge volume) kinetically enhanced copper vapor laser developed in our laboratory and capable of generating maximum power of ∼80 W (at ∼9.8 kHz). The efficiency of the laser was ∼1.4% and beam divergence of ∼3.5 mrad in a plane-plane standard multimode cavity. For the first time performance of unstable CAT-EYE resonator is demonstrated with a CVL/KE-CVL. On using unstable CAT-EYE resonator the divergence of the laser beam reduced to ∼0.22 mrad (∼20-fold reduction as compared to conventional plane-plane cavity), ∼40 W output power and with excellent misalignment tolerance. The laser output power was found to be within ∼5% drift/decline with misalignment angle of about 4 mrad between the mirrors. This is a significant improvement in comparison to standard conventional unstable resonator (M ∼ 50) CVL where ∼0.5 mrad divergence is achieved with power drift/decline of about 45% at ∼4 mrad misalignment angle.Off-axis unstable CAT-EYE unstable resonator was also demonstrated for the first time with further reduction in beam divergence to ∼0.13 mrad and with output power of ∼28 W. The misalignment tolerance was found to be highest in case of off-axis unstable CAT-EYE resonator with decline/drift in laser power of only ∼10% for misalignment angle as high as ∼8 mrad. Performance with intra-cavity apertures in plane-plane type CAT-EYE resonator for transverse mode control is also presented for the first time in CVLs. It is observed that the laser beam divergence reduces significantly to 1.25 mrad (a factor of 2) on using an aperture of ∼3.5 mm at the CAT-EYE reflector as compared to its normal (R = F = d) configuration without aperture. In case of stable CAT-EYE resonator the average beam divergence reduces from 8 mrad to 4 mrad (factor of 2) on using intra-cavity aperture of about 3 mm. It was also observed that high misalignment tolerance was retained on using intra-cavity apertures in almost all the CAT-EYE resonators. Use of intra-cavity mesh was also demonstrated for the first time with stable CAT-EYE resonator for improving the beam focus-ability. Average beam divergence was reduced by a factor of 2.5 (from 8 mrad to 3 mrad) on using intra-cavity mesh. These new configurations in CAT-EYE resonators in KE-CVLs are found to be effective in improving and controlling the laser beam divergence significantly with additional characteristic of high misalignment tolerance.     

120 W的二极管泵浦Nd:YAG绿光激光器

对激光二极管泵浦的NdYAG声光调Q腔内倍频固体激光器的折叠腔型进行了研究,当泵浦功率达800 W时,在V型腔上实现了脉宽为80 ns、重复频率为10 kHz、发散角为6 mrad、绿光功率为112 W的输出;在Z型腔上实现了脉宽为95 ns、重复频率为10 kHz、发散角为4 mrad、绿光功率为120 W的输出.比较两种腔型的实验结果可看出,Z型腔由于插入的光学元件较多,腔长较长,输出激光的脉宽较宽,但输出激光的光束质量有明显的提高.     

钇铝石榴石对撞增强型相位共轭腔的研究

报道了一种新型的相位共轭腔——对撞型钇铝石榴石受激布里渊散射相位共轭激光腔,实验结果发现该腔具有较低的启动阈值和100mJ以上的输出能量,它能输出稳定的20ns左右的自调Q脉冲,发散角为1．3mrad。在一定范围内,抽运电压越高,输出脉宽越窄;相位共轭腔越长,输出脉宽越宽;聚焦透镜对输出脉宽也有影响,焦距越短,脉宽越窄;焦距与介质池相对长点,输出能量相对高,远场发散角相对小些。实验给出了不同条件下的输出能量、脉冲宽度和光束发散角的情况。     

变反射率镜非稳腔优化研究—超高斯途径

分析了超高斯变反射率镜非稳腔的腔模和输出特性。以最高输出光束亮度为目标就其腔参数进行了优化研究和设计。在２０ｍｍ口径钕玻璃激光介质上采用这种腔结构进行了实验研究，获得了数十焦耳近衍射极限的高亮度激光输出。     

高功率LD阵列泵浦激光器小型化研究

为满足一些武器装备对激光系统小型化及输出激光光斑均匀性较高的要求,通过设计LD侧面对称半环状泵浦的泵浦方式,使得输出的激光光斑形状基本为圆形,激光光斑的均匀性有了较大提高.采用凹面全反射镜补偿热效应以及设计紧凑激光谐振腔型,在注入电流60 A、频率为20 Hz时,得到平均单脉冲能量为96 mJ (脉冲能量波动小于6%)、脉宽为10 ns、发散角为3 mrad的近似圆形激光输出,激光系统在高温50℃时工作稳定.     

1.444 mm Nd:YAG激光器的实验研究

 在理论分析的基础上设计了直腔结构1.444 mm Nd:YAG激光器，并进行了实验研究。获得了1.444 mm激光输出，当泵浦能量为55 J时，其最高静态激光输出310 mJ。电-光转换效率为0.56%，斜效率为0.81%。并实现了1.444 mm调Q输出，脉冲输出能量18 mJ，脉宽150 ns。     

小型多功能CO2激光器

研制了一种小型多功能CO2激光器。该激光器可以单脉冲、重频或连续方式输出,并可实现输出脉冲频率的编码及波长调谐。激光器谐振腔采用光栅一级振荡,零级输出的工作方式,分别利用声光调Q技术和脉冲放电技术实现了百ns至亚ms量级的脉冲激光输出。详细介绍了该激光器中基于光学角反射器原理设计的光栅调谐定向输出装置,并对其进行了理论计算和论证,实现了不同波长激光的定向、定位输出,获得调谐激光输出谱线超过60条,谱线分辨率优于0.01μm。激光器脉冲重复频率1Hz～10KHz连续可调,输出波长调谐范围9.2μm～10.8μm,激光器连续输出最大功率8W,重复频率1KHz时最小激光脉宽180ns,峰值功率4062W。该激光器在激光与物质相互作用科学领域,特别是激光对物质作用与破坏机理的研究方面具有重要的应用价值。