共查询到20条相似文献,搜索用时 15 毫秒
1.
The mechanism of the slowly opened Q-switch operation was investigated thoroughly. Maximum energy extraction from the resonator
could be optimized, and the smallest output beam divergence could be achieved. In this article, we present a detailed analysis
that has numerically verified the mode-selection mechanism in the slowly opened Q-switch operation, and the degree of the
smaller output laser beam divergence that has been achieved. The mechanism of the slowly opened Q-switch operation is the
inherent advantage of the passive saturable absorber in this operation. We can use the maximum energy extraction and the smallest
output beam divergence results of the slowly opened Q-switch operation to design and optimize various passive saturable absorbers:
plastic dye sheets, LiF:F2− color center crystals, Cr4+: YAG crystals, RG1000 color glass filters, and the single crystal semiconductor saturable absorber wafers that are in developed
in our microchip laser systems. 相似文献
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一种新型固体Q开关——Cr^4+:YAG的实验研究 总被引:4,自引:1,他引:3
对一种适用于Nd^3+:YAG激光系统的新型波动Q开关-掺铬钇铝石榴石(Cr^4+:YAG)进行了实验研究,得到单脉冲量为145mJ,脉宽为30~40ns,效率接近1%,动静比达40%以上的结果。 相似文献
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The behaviour of passively Q-switched solid-state lasers containing intracavity optical parametric oscillators (OPOs) is described, and a model to optimize this system‘s performance is developed. Meanwhile, an Nd:YAG laserpumped KTiOPO4 (KTP) intracavity OPO for eye safe laser output is studied experimentally. A Brewster-oriented bis-(4-dimethylaminodithiobenzil)-nickel (BDN) dye film is employed in laser cavity, which plays the double role of a passive Q-switch and a Brewster plate, to Q-switch the light to increase its intensity and polarize the light so that the polarization plane of fundamental irradiation is perpendicular to the Z-axis of KTP serving as the OPO nonlinear crystal, thereby providing type Ⅱ phase matching conditions to generate 1.572μm eye-safe signal laser. Eye-safe signal radiations of 6.6mJ per pulse at 1.572μm wavelength and pulse width as narrow as 6.0ns (FWHM) were obtained. Peak power was up to 1.1MW. 相似文献
6.
A type of electro-optic Q-switch is designed by using optically active crystal La3Ga5SiO14 (abbreviated as LGS), in which the polarization plane gyration and electro-optic effect exist simultaneously. The configuration of the Q-switch is based on the consideration that the total rotation angle of the polarization plane of the polarized laser is zero, while the laser in the cavity propagates through the Pockels cell back and forth. The Q-switch placed in a Nd3 +:YAG laser behaves normally, like those without optical activity. Compared with the DKDP Q-switch, the LGS Q-switch has more superiorities, which make it a suitable replacement for the DKDP Q-switch in lasers with medium-output energy. 相似文献
7.
In the experiment, we have demonstrated the performance of a laser-diode, end-pumped, doubly Q-switched YVO4/Nd:YVO4 laser with both a BBO electric-optic (EO) Q-switch and Cr4+:YAG saturable absorber. At a maximum incident pump power of 15 W and an EO Q-switch repetition rate of 8 kHz, the stable laser pulses with the pulse duration 5.28 ns, the single pulse energy 0.14 mJ, and the pulse peak power 26 kW are obtained. The experimental results show that the double Q-switched laser with EO and Cr4+:YAG can generate the shorter pulse and the higher peak power in comparison to singly Q-switched laser with EO. 相似文献
8.
C. Theobald M. Weitz R. Knappe R. Wallenstein J.A. L’huillier 《Applied physics. B, Lasers and optics》2008,92(1):1-3
This paper reports on a passively mode-locked and Q-switched Nd:YVO4 laser generating picosecond pulses with an average output power exceeding 7 W. In a first step Q-switch mode-locking was
obtained by self Q-switching of a mode-locked oscillator with appropriate cavity design, pump power and output coupling. In
a second system the Q-switching was actively controlled and stabilized by modulating the resonator internal losses with an
acousto-optic modulator. In the Q-switch mode-locking operation the laser provided 12.8 ps long mode-locked pulses with a
repetition rate of 80 MHz. The repetition rate of the Q-switch envelope was 185 kHz. The maximum pulse energy of a single
ps pulse was 0.55 μJ which is 5.5 times the pulse energy measured for cw mode locking. The total energy of the pulses within
the Q-switch envelope was 42 μJ.
PACS 42.55.Xi; 42.60.Fc; 42.60.Gd 相似文献
9.
采用谐振腔内插入声光调制器(AOM)的方法获得了小型CO2激光器的高重频、窄脉宽、高峰值功率输出。通过分析CO2激光器声光调Q的工作原理,利用基于小信号增益和饱和光强的耦合输出数学模型给出了激光器最佳输出镜透过率的数值解,并运用相关实验装置对该数学模型进行了实验验证。理论分析和实验结果均表明:该声光调Q CO2激光器的最佳输出镜透过率为39%。研究了激光器输出性能随脉冲重复频率的变化规律,当脉冲重复频率〉1 kHz时,激光器输出峰值功率下降,这与CO2分子上能级寿命有关,并受声光调Q开关热效应的影响。实验中获得的激光器脉冲频率在1 Hz~100 kHz可调。在脉冲频率为1 kHz时,获得的激光脉冲宽度为156 ns,脉冲峰值功率为10 kW,且稳定性较好,非常适合于作激光与物质相互作用的光源。 相似文献
10.
A polymeric multilayered mirror doped with a saturable dye worked as a passive Q-switch of a laser-diode-pumped Nd(3+):YVO4 microchip laser. The multilayered mirror consisted of alternately spin-coated layers of polyvinylcarbazole (PVK) and cellulose acetate on a glass substrate. A dye of bis-(dimethylaminodithiobenzil)-nickel was doped in one of the layers of PVK, providing the repetitively Q-switched pulses. The pulse width and repetition rate were 4 ns and 68 kHz, respectively, for a laser-cavity length of 5 mm, and the average and the peak power were 40 mW and 156 W, respectively, for the highest pump power of 435 mW. The dependence of the Q-switched characteristics on the pump power and on the concentration of the doped dye is described. 相似文献
11.
LD泵浦的Nd:YAG调Q激光器腔内倍频研究 总被引:1,自引:0,他引:1
DPL的调Q倍频是获得高重复率绿光输出的有效方法,本文研究了这种激光器的动态特性,提出存在使转换效率最高的最佳非线性耦合系数,它是调Q时反转粒子数超阈值倍数的函数.实验用国产200mWR的MQW—LDA泵浦Nd:YAG激光器,声光调Q,KTP腔内倍频,输出0.4μJ的倍频光,脉宽70ns,峰功率6W. 相似文献
12.
V.V. Ter-Mikirtychev 《Optics & Laser Technology》1997,29(4):229-231
A new passive Q-switching geometry of a laser cavity has been proposed. In the proposed scheme, the volume of the passive Q-switch just partially overlaps the intracavity laser beam cross-section, leading, however, to the entire beam modulation. This technique was applied for passive Q-switching of a flash-lamp pumped multimode YAG:Nd3+ laser by LiF:F2− crystals. The giant pulse laser action threshold has been detected in the proposed geometry, and is lower than that in the scheme where the passive Q-switch operates in the traditional manner. Stable giant pulse oscillation of 1064 nm wavelength with a pulse duration of 24 ns, pulse energy of 450 mJ, and pulse repetition rates of up to 100 Hz, have been obtained. 相似文献
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ZHANG Qidi ZHAO Shengzhi ZHANG Xingyu WANG Qingpu ZHENG Jia' an SUN Lianke ZHANG Shaojun 《中国光学快报(英文版)》2001,10(1)
By using a laser-diode as pump source, a Cr4+ :YAG crystal as saturable absorber for passive Q-switch and a KTP as intracavity frequency doubling crystal, we have realized the green Q-switched laser output at 0.5295 μm from a Nd: S-FAP crystal. Output green laser characteristics, such as average power, single pulse energy, pulse width, repetition rate for different small-signal transmission of Cr4+ :YAG and different pump power, were measured. Meanwhile, the coupling rate equations of intracavity frequency doubling with Cr4+ :YAG as passive Q-switch were given and the numerical solution of equations agreed with the experimental results. 相似文献
15.
ZHANG Qidi ZHAO Shengzhi ZHANG Xingyu WANG Qingpu ZHENG Jia' an SUN Lianke ZHANG Shaojun 《Chinese Journal of Lasers》2001,10(1):19-23
By using a laser-diode as pump source, a Cr4+ :YAG crystal as saturable absorber for passive Q-switch and a KTP as intracavity frequency doubling crystal, we have realized the green Q-switched laser output at 0.5295 μm from a Nd: S-FAP crystal. Output green laser characteristics, such as average power, single pulse energy, pulse width, repetition rate for different small-signal transmission of Cr4+ :YAG and different pump power, were measured. Meanwhile, the coupling rate equations of intracavity frequency doubling with Cr4+ :YAG as passive Q-switch were given and the numerical solution of equations agreed with the experimental results. 相似文献
16.
Q-switch operation of a c-cut Tm (5 at %), Ho (0.3 at %):YAP laser at 2132 nm wavelength were reported in this paper. In the temperature of 77 K, the Tm, Ho:YAP crystal was double end-pumped by a 21.4-W fiber-coupled laser diode (LD) at the center wavelength of 794.3 nm. A 5.29-W Q-switch output power was acquired at pulse repetition frequency (PRF) of 10 kHz, corresponding to an optical-optical conversion efficiency of 24.7% and a slope efficiency of 28.1%. The energy per pulse of 3.57 mJ in 38 ns was achieved at 1.25 kHz with the peak power of 93.9 kW. 相似文献
17.
The threshold operation and performance of a high pulse repetition frequency Nd/YAG laser are discussed. A rotating mirror Q-switch was used, and detailed studies of the variation of Q-switched threshold with motor frequency, and of the pulse build-up time with input power have been carried out. The results indicate that the switching angle varies with mirror reflectivity but is practically independent of resonator length. The latter is attributed to thermal lens action in the laser rod modifying the nominally plane parallel resonator configuration thereby leading to a spherical configuration. Under these conditions, the switching angle becomes independent of resonator length, but depends strongly on the induced focal length of the lens (laser rod). The degrading effect on the Q-switched laser performance of the mis-match at the laser rod surfaces is then discussed and finally the conditions for achieving maximum energy output in a single pulse are derived and experimentally verified. 相似文献
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Continuous wave and AO Q-switch operation of a b-cut Tm,Ho:YAP laser with dual wavelengths pumped by a laser diode of 792 nm 总被引:1,自引:0,他引:1
Continuous wave (CW) and AO Q-switch operation of a b-cut Tm,Ho:YAP laser with dual wavelengths were reported in this paper.
In the temperature of 77 K, the b-cut Tm,Ho:YAP crystal was double endpumped by a 7.21-W fiber-coupled laser diode (LD) at
the center wavelength of 792 nm. A 1.17-W Q-switch output power was acquired at pulse repetition frequency (PRF) of 10 kHz,
corresponding to an effective optical-optical conversion efficiency of 25.9% and an effective slope efficiency of 31.5%. The
energy per pulse of 0.46 mJ in 100 ns was achieved at 2.5 kHz with the peak power of 4.6 kW. 相似文献
20.
选择含能聚合物聚叠氮缩水甘油醚(GAP)作为激光烧蚀微推力器的工质,分析了红外染料掺杂对激光烧蚀GAP工质推进性能的影响.通过对比掺杂红外染料GAP在不同激光功率密度、掺杂浓度、靶材厚度和激光烧蚀模式下的推进性能数据和烧蚀羽流,初步探索了掺杂红外染料GAP工质的推进性能优化方式.实验结果表明:透射式激光烧蚀模式下,激光能量的指数衰减特性和掺杂红外染料GAP的强黏性使得烧蚀羽流中易存在未充分烧蚀的工质; GAP的推进性能受红外染料掺杂浓度和靶材厚度的综合影响,当靶材厚度与激光吸收深度接近时,靶材充分吸收激光能量使中心烧蚀区达到化学能释放的温度阈值,同时沿激光传播方向未充分烧蚀的质量最少,此时推进性能达到最优值.反射式下掺杂红外染料的聚合物的激光烧蚀过程遵循"先吸收激光能量先喷射"的规律,工质分解充分,推进性能优于透射式. 相似文献