共查询到19条相似文献,搜索用时 109 毫秒
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本文报道板条激光器的热稳运行,在150W至10000W的泵浦功率下输出发散角基本保持不变,最大输出功率大于150W;并绘出了腔内插入柱面镜,以压缩输出激光发散角的初步结果. 相似文献
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给出了放电型高增益非稳腔KrF激光器具有衍射极限的激光模式建立的时间与非稳腔放大率和腔长之间的关系。实验对放大率M=8,腔长L=1.75m和放大率M=13.3,腔长L=1.85m的正支共焦非稳腔在不同增益下输出光的发散角进行了测量。充电电压为30kV,发散角分别是39倍衍射极限和33倍衍射极限。当充电电压降至26kV,即降低腔内介质的增益时,它们的发散角分别是20倍和5倍衍射极限。表明了具有衍射极限的模式建立时间受放大率、腔长以及饱和效应的影响。要得到衍射极限光,其衍射极限光的建立时间必须小于饱和时间。 相似文献
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从泵浦光与腔模的空间匹配函数出发,讨论了泵浦光的发散角、焦点位置等因素对激光系统效率的影响。发现在旁轴近似下,匹配函数的最大值随泉浦光发散角的增大而增大,在考虑到像散的影响后,得到泵浦光发散角的参考值。 相似文献
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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。 相似文献
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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. 相似文献
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从掺镱光纤激光器腔内的激光场出发,讨论了掺镱光纤激光器腔内的噪声信号对锁模启动的影响,并针对我们设计的8字腔超短脉冲光纤激光器进行了研究。通过对激光器腔内锁模过程的分析发现:在泵浦功率为214.75 mW时,自行研制的8字形腔掺Yb3+光纤激光器在未注入噪声信号时,输出端在30~50 s内获得稳定的锁模脉冲激光输出;在腔内注入脉宽30 ns,频率10 kHz,平均功率0.2 mW的脉冲噪声后,输出端在1~2 s内获得同样稳定的锁模脉冲激光输出。实验结果表明,注入激光器谐振腔内一定的噪声信号,可加速锁模的启动。 相似文献
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本文从菲涅耳衍射积分公式出发研究了激光器非稳腔输出环状光束在空间的传输规律.由轴上光强的极值点位置给出了划分非稳腔传输空间的近场、中场和远场区域公式.理论计算结果表明,非稳腔输出端环状光束在中场区域激光能量逐渐向轴心方向转移,而在远场变为爱里型圆盘状光束的过程.在非稳腔脉冲TEA CO_2激光器上测得的实验结果与理论计算结果很好地符合. 相似文献
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模拟了强流电子束泵浦下,激光腔内的反应动力学过程,及不同注入时间、不同注入强度下注入锁定的激光生成、放大和输运过程。对实际非稳腔使用了一维伸展近似,并采用了预估—校正方法对光子输运方程进行求解。模拟结果表明,激光生成阶段,注入种子光源后,激光输出质量明显改善,使自发辐射部分受到了明显的抑制。得到了在不同注入强度、注入时间以及放大倍数下的激光输出的光谱特性,能量及各种效率的关系。发现锁定效果最佳时的注入时间出现在小信号增益峰值处。 相似文献
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球面角锥棱镜非稳腔钕玻璃激光器 总被引:2,自引:1,他引:1
为了将虚共焦非稳腔输出光束质量高和角锥棱镜谐振腔具有免调试的优点结合到一起,提出了用球面角锥棱镜构成虚共焦非稳腔的方案。利用已有虚共焦非稳腔钕玻璃激光器,设计加工了一球面角锥棱镜非稳腔钕玻璃激光器。模拟计算了两谐振腔输出光束的模式分布,然后对两钕玻璃激光器进行了实验对比研究。结果表明:实验得到的模式分布与模拟计算结果相吻合,球面角锥棱镜非稳腔钕玻璃激光器与虚共焦非稳腔钕玻璃激光器分别获得了最大2176.9J和2340.6J的能量输出,二者的电光效率与束散基本相同,分别为4.3%,0.30mrad和4.6%,0.26mrad。 相似文献
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In this paper we present calculations of the three-dimensional mode structure and output beam characteristics of unstable resonator with turbulent active medium. The calculations of the output beam are carried out in the Fresnel approximation using the well-known iterative method [1]. The active medium is modeled as a series of phase screens with Kolmogorov statistics. The dependence of output radiation parameters of the gas flow laser with unstable resonator on the strength of turbulence in active medium and parameters of resonator is under consideration. 相似文献
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In this paper the characteristics of the output beam of a toric unstable resonator are investigated. Based on the Fresnel–Kirchhof integral and using numerical methods, the performance of toric unstable resonators is simulated and its output beam characteristics are also evaluated. Geometrical resonator parameters, i.e. Fresnel number and magnification as well as the output coupler diameter, are considered in this investigation. The radial and azimuthal modes of the resonator are calculated and the modal behavior of the resonator is described according to geometrical parameters. The power extraction for each specific laser mode has also been inspected by calculating the finesse factor. Using an iteration mode convergence diagram, the mode discrimination of the resonator is investigated. 相似文献
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Bijendra Singh S.R. Daultabad V.V. Subramaniam Ashim Chakraborty 《Optics Communications》2008,281(24):6080-6090
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. 相似文献
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Design of optical coupling systems between two-dimensional quasi-stadium laser diodes and single-mode optical fibers 总被引:1,自引:0,他引:1
Optical coupling systems between a two-dimensional quasi-stadium laser diode and single-mode optical fibers using gradient-index
rod lenses are designed for both stable and unstable laser resonators for the first time. A novel numerical approach using
a combination of the extended Fox-Li calculation method and Gaussian beam transformations is proposed. In the case of a stable
laser resonator, two kinds of beam propagation modes appear, namely the axis mode, in which an optical beam propagates along
the cavity axis, and the ring mode, in which optical beams propagate along the diamond-shaped trajectory. The coupling efficiencies
are found to be 54% for the axis mode and 52% for the ring mode. In contrast, an unstable laser resonator exhibits complicated
modes, in which several highly directional beams are emitted from the end mirrors. The total coupling efficiency for these
output beams is calculated to be 9.6%. The 3-dB tolerances for the lens pitch and alignment angles of the gradient-index rod
lenses are also discussed. 相似文献