高功率二极管泵浦腔内倍频激光器

 成功研制了一台高功率二极管泵浦声光Q开关腔内倍频Nd:YAG激光器。当泵浦功率约为350W时，采用透过率为30%的输出耦合镜，调Q激光输出功率32.5W，脉宽约200ns，重复频率7kHz；采用Ⅱ类匹配KTP晶体腔内倍频，获得了32.5W的绿光输出，脉宽约120ns。输出光束平滑，远场为类高斯分布，测得的光束质量因子为3.6。     

LD侧面泵浦Nd:GdVO4 532 nm绿光激光器

为了获得高功率窄脉宽532 nm绿光激光输出,通过高重复频率声光驱动调Q技术和LD侧面泵浦Nd∶GdVO4技术,获得高功率线偏振1 064 nm激光输出.采用内腔倍频方式,对非线性晶体KTP进行频率变换,实现高功率窄脉宽绿光激光输出.在电源输入电流30 A,调Q驱动频率10 kHz的条件下,获得最高功率30 W线偏振1 064 nm激光输出,脉宽30 ns,倍频KTP晶体获得23.4 W的532 nm绿光输出,1 064 nm到532 nm转化效率为78％.实验结果表明:通过声光调Q技术和LD侧面泵浦Nd∶GdVO4技术,可以实现高功率线偏振窄脉宽1 064 nm激光输出,倍频非线性晶体KTP可获得高功率窄脉宽532 nm激光.     

LD侧面泵浦Nd∶GdVO4 532 nm绿光激光器

为了获得高功率窄脉宽532 nm绿光激光输出,通过高重复频率声光驱动调Q技术和LD侧面泵浦Nd∶GdVO4技术,获得高功率线偏振1 064 nm激光输出。采用内腔倍频方式,对非线性晶体KTP进行频率变换,实现高功率窄脉宽绿光激光输出。在电源输入电流30 A,调Q驱动频率10 kHz的条件下,获得最高功率30 W线偏振1 064 nm激光输出,脉宽30 ns,倍频KTP晶体获得23.4 W的532 nm绿光输出,1 064 nm到532 nm转化效率为78%。实验结果表明:通过声光调Q技术和LD侧面泵浦Nd∶GdVO4技术,可以实现高功率线偏振窄脉宽1 064 nm激光输出,倍频非线性晶体KTP可获得高功率窄脉宽532 nm激光。     

LD抽运Nd:GdVO4的激光性能研究

利用LD端泵NdGdVO4晶体,实现了激光器的1 063 nm连续和调Q激光输出.在连续激光输出实验中,在泵浦功率为20.2 W时,得到最高的光-光转换效率为55.0%,斜效率为59.1%,此时输出功率为11.5 W;在泵浦功率为33.7 W时,得到16.7 W的最大激光输出.在调Q实验中,当重复频率为10 kHz时,获得脉宽6.5 ns,能量340 μJ,峰值功率52.3 kW.当重复频率为30 kHz时,获得脉宽14.5 ns,平均输出功率5.18 W,峰值功率11.9 kW.     

高效LD侧面泵浦腔外倍频绿光激光器

为满足激光加工、激光彩色显示、数据存储、医疗卫生和科研等领域对绿光激光器的需要,研制了一台高倍频效率、窄脉宽侧面泵浦腔外倍频的YAG/LBO绿光激光器。分析并计算了腔外最佳聚焦参数,确定了透镜的最佳聚焦焦距。实验中,利用808nm激光二极管侧面泵浦Nd:YAG晶体,使用BBO晶体进行加压式调Q,采用四分之一波片补偿Nd:YAG晶体的热退偏,最终实现了重复频率1kHz、输出功率10.7W的1 064nm输出,最大单脉冲能量为10.7mJ。在此基础上,采用Ⅰ类温度相位匹配LBO晶体对基频光进行腔外倍频,获得了重复频率1kHz、脉宽21ns、最大输出功率6.04W的532nm准连续绿光输出,倍频效率高达59.3%。     

二极管侧面抽运Nd:YAG/KTP腔内倍频百瓦级绿光激光器

为了获得百瓦级激光二极管侧面泵浦绿光激光器,设计了双棒串接、双声光调Q的Z型谐振腔结构.依据光束传输矩阵,通过软件模拟并计算了激光晶体内基模半径随屈光度的变化以及倍频晶体附近腔内光场在子午面和弧矢面内的分布情况,筛选出理想的谐振腔参数.在总泵浦功率1 080 W,声光调Q重复频率为10 kHz时,获得532 nm绿光最大平均输出功率为174.1 W,脉冲宽度为160 ns,光-光转换效率为16.1%,光束质量因子M2x＝9.63,M2y＝9.78.实验结果表明,使用双棒串接、双声光调制Z型腔结构,可以获得百瓦级高功率高光束质量532 nm绿光输出.     

二极管侧面抽运Nd∶YAG/KTP腔内倍频百瓦级绿光激光器

为了获得百瓦级激光二极管侧面泵浦绿光激光器,设计了双棒串接、双声光调Q的Z型谐振腔结构。依据光束传输矩阵,通过软件模拟并计算了激光晶体内基模半径随屈光度的变化以及倍频晶体附近腔内光场在子午面和弧矢面内的分布情况,筛选出理想的谐振腔参数。在总泵浦功率1080W,声光调Q重复频率为10kHz时,获得532nm绿光最大平均输出功率为174.1W,脉冲宽度为160ns,光-光转换效率为16.1%,光束质量因子M2x＝9.63,M2y＝9.78。实验结果表明,使用双棒串接、双声光调制Z型腔结构,可以获得百瓦级高功率高光束质量532nm绿光输出。     

LD侧面泵浦电光调Q532nm脉冲激光器

 为了实现高可靠、窄脉宽、高峰值功率激光输出,采用侧面泵浦技术和电光调Q技术,设计出一种激光二极管侧面泵浦电光调Q全固态绿光激光器。采用结构简单、紧凑的平-平腔设计,其端镜和输出镜均为平面镜,获得较稳定的侧面泵浦Nd∶YAG腔外倍频KTP脉冲绿光激光输出。当泵浦电流为120A,重复频率为600Hz时,获得脉冲绿光的最高输出平均功率为3.62W,1064nm到532nm的转换效率为15.3%,其脉宽为21ns,峰值功率为300kW, 单脉冲能量为6.01mJ。实验结果表明：该激光器稳定性可靠,输出激光脉宽较窄、峰值功率高。     

高效三倍频全固态Nd∶YAG/LBO紫外激光器

报道了一种侧面泵浦Nd∶YAG、声光调Q、LBO晶体腔外倍频和三倍频的355 nm准连续波紫外激光器.采用结构简单、紧凑的平-凹腔设计,在152 W的泵浦功率下,重复频率5 kHz时,获得平均功率1.62 W的355 nm TEM00模激光输出,三倍频的转换效率为25%;重复频率1 kHz时,获得平均功率518 mW、单脉冲能量518 μJ、脉宽17 ns、峰值功率高达30 kW的紫外激光输出.     

高效率Nd:YVO4/LBO临界相位匹配脉冲绿光激光器

报道了一种利用激光二极管（LD）端面泵浦Nd:YVO4晶体,声光调Q,LBO临界相位匹配腔内倍频的高效率、小体积、风冷绿光激光器。分析了不同偏振光泵浦的情况下,激光晶体对泵浦光的吸收特性。由分析得出,采用部分偏振光泵浦,可以提高激光晶体对泵浦光吸收均匀性,改善基波畸变,获得高转换效率激光输出。实验中,在泵浦光功率为33 W、声光调Q重复频率为20 kHz时,得到脉宽为23.96 ns、平均功率为15 W的1064 nm基频光输出。经倍频后,得到平均功率为11.2 W的绿光输出,倍频效率为74.6%,总体光-光转换效率为34%。在输出功率为10 W时,测得1 h内输出功率不稳定度为0.512 2%,水平方向和竖直方向的光束质量因子M2分别为1.2和1.1。     

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     

大功率TEA CO2激光器非稳腔的设计与实验

相比于传统稳腔高功率TEA CO2激光器,如何在不降低功率的基础上,改善其光束质量一直研究者关心的问题。本文在原有稳腔激光器的基础上,设计了三组望远镜虚共焦腔镜,给出了完整的设计过程并进行了理论分析。同时对不同组的非稳腔激光器进行了对比实验研究,结果表明非稳腔能够在保证高单脉冲能量的基础上极大地改善激光远场发散角,其中最佳腔镜组合能够达到单脉冲能量13.7J,其发散角为1mrad（稳腔为2.4mrad）,激光脉宽50ns（稳腔为98ns）。这就为此种类型激光器应用于激光制造领域奠定了基础。     

拱形激光二极管侧抽运Nd∶YAG固体激光器的实验研究

详细阐述了同心抽运、同心冷却的激光二极管紧包侧抽运Nd∶YAG激光器的实验研究工作。这种抽运结构使晶体内的增益场与谐振腔基模实现了良好的匹配,易于得到良好的光束质量和大能量输出,基模提取效率高。模拟分析了晶体内的增益场以及横截面内的温度分布,从不同角度探讨了激光二极管的温度特性对器件工作的影响。研究了晶体的热致退偏效应对器件调Q工作的影响,并且初步探讨了不同腔长、不同腔型下器件的工作情况,这些实验结果对进一步优化使用这种抽运结构有指导意义。所设计的激光器在工作频率6Hz时,得到了斜效率为44.3%的多模调Q输出。在抽运能量735mJ时,得到最大输出能量135mJ,脉宽7.6ns的调Q脉冲,光光效率为18.4%,插头效率为11.0%,光束发散角小于1.5mrad。     

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。     

Depolarization loss compensated resonator for electro-optic Q-switched solid-state laser

A novel laser resonator for compensating depolarization loss that is due to thermally induced birefringence in active rod is reported. As this new structure being applied to an electro-optic Q-switched LDA side-pumped Nd:YAG laser operating at a repetition rate of 1000 Hz, substantial reduction in depolarization loss has been observed, the output pulse energy is improved about 56% from that of a traditional resonator without compensation structure. With incident pump energy of 450 mJ per pulse, linearly polarized output energy of 30 mJ per pulse is achieved, the pulse duration is less than 15 ns, and the peak power of pulse is about 2 MW. The extinction ratio of laser beam is better than 10:1, and the beam divergence is 1.3 mrad with beam diameter of around 2.5 mm.     

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。     

抽运角锥棱镜腔电光调Q固体激光器

利用角锥棱镜的退偏效应实现了电光调Q固体激光器的偏振耦合输出.器件采用热传导冷却半圆柱面LD阵列侧向泵浦Nd∶YAG泵浦几何,获得在20 Hz运行条件下,脉冲能量163 mJ/pulse、脉冲宽度6.5 ns、发散角3.5 mrad、能量稳定性±2.8％、光光效率16.7％的理想性能.与传统平行平面腔相比,具有效率高、峰值功率大、输出能量和脉宽可调,且输出稳定等优点.     

LD抽运角锥棱镜腔电光调Q固体激光器

利用角锥棱镜的退偏效应实现了电光调Q固体激光器的偏振耦合输出.器件采用热传导冷却半圆柱面LD阵列侧向泵浦Nd:YAG泵浦几何,获得在20 Hz运行条件下,脉冲能量163 mJ/pulse、脉冲宽度6.5 ns、发散角3.5 mrad、能量稳定性土2.8%、光光效率16.7%的理想性能.与传统平行平面腔相比,具有效率高、峰值功率大、输出能量和脉宽可调,且输出稳定等优点.     

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.     

电子束泵浦百焦耳级准分子激光实验研究

利用“闪光二号”相对论电子束加速器研制了百焦耳级ＸｅＣｌ和ＫｒＦ准分子激光器，激光器激活体积２４ｌ，输出口径２０×２０ｃｍ２，泵浦功率密度１．５～２．０ＭＷ／ｃｍ３。ＸｅＣｌ激光器最大能量１３６Ｊ，波长３０８ｎｍ，脉宽５０～１００ｎｓ，峰值功率１．５ＧＷ，采用虚共焦非稳腔技术，束散角达１．３ｍｒａｄ；ＫｒＦ激光最大能量１５７Ｊ，波长２４８ｎｍ，脉宽８０～１００ｎｓ，峰值功率２ＧＷ。