Theoretical Analysis on the Simultaneous Operation of a Color-Center Laser and a Q-Switched Nd: YAG Laser

The simultaneous operation for the Q- switched Nd: YAG laser at 1.06 and the tunable color-center laser over 1.12～1.26 μm has been realized by using a LiF: F2- color-center crystal both as the Q-switcher for the Nd:YAG laser and as the active medium for the color-center laser. The interaction of the two lasers has been analyzed and calculated with the rate equations. The pulse duration of YAG laser is compressed, in agreement with the experimental results.     

激光二极管泵浦Nd：FAP激光器

报道激光二极管泵浦的掺钕氟磷酸钙固体激光器，该器件在重复频率为１００Ｈｚ的准连续状态下运行，当耦合输出透过率为８％时，得到３１％的斜效率，比较了ＦＡＰ和ＹＡＧ这两种介质的激光器的性能，理论分析得出的两者的阈值泵浦功率的相对值与实验结果相一致，并证实ＦＡＰ是一种有前途的适合激光二极管泵浦的激光介质。     

Studies on Nd:YAG Single-pass Amplifiers for High-power Q-switched Laser System

The output of Nd∶YAG single-pass laser amplifiers is studied analytically and experimentally. Methods of analysis for single-pass Nd∶YAG laser amplifier are presented. A flashlamp-pumped Q-switched Nd∶YAG oscillator/amplifier laser system has been developed with the average output power of 121.5 W.     

Studies on Nd∶YAG Single-pass Amplifiers for High-power Q-switched Laser System

The output of Nd∶YAG single-pass laser amplifiers is studied analytically and experimentally. Methods of analysis for single-pass Nd∶YAG laser amplifier are presented. A flashlamp-pumped Q-switched Nd∶YAG oscillator/amplifier laser system has been developed with the average output power of 121.5 W.     

Emission Spectrochemical Analysis of Metals Using a Nitrogen Laser

Comparative studies of the possibilities of using pulsed nitrogen and Nd:YAG lasers for emission spectrochemical analysis of copper-zinc alloys have been made. The nitrogen laser developed on the basis of the commercial excimer laser provided an energy of radiation pulses of 5 mJ with an error of less than 0.8% at a repetition frequency of 100 Hz. The high stability and the high pulse repetition frequency of the nitrogen laser were attained due to the additional high-speed fan inside the laser chamber, which provided agitation and circulation of the gas mixture. It has been shown by experiment that the spectral emission of the plasma formed by means of the nitrogen laser is characterized by intensity fluctuations with a root-mean-square deviation of 1.4%, whereas in the case of using an Nd:YAG laser it was 14.3%. The advantages of the nitrogen laser that are due to the increased signal-to-background ratio and the suppression of the selective evaporation effect have been revealed.     

激光二极管泵浦单频连续工作的Nd：YAG激光器

在国内首次报道了激光二极管泵浦单频连续工作的Ｎｄ：ＹＡＧ激光器，采用扭摆模腔技术方法，在８０８ｎｍ激光二极管连续泵浦下，取得１０６４ｎｍ连续单频工作，输出功率５５ｍＷ的结果，泵浦阈值２７６ｍＷ，斜率效率２３％，线宽小于２５ＭＨｚ（受仪器测量精度限制）。     

Cr^4＋：YAG在对撞脉冲锁模的Nd：YAG激光器中实现被动锁模的研究

在理论上提出了Ｃｒ＾４＋：ＹＡＧ作为可饱和吸收体在Ｎｄ：ＹＡＧ激光器中实现被动锁模的可能性，运用速率方程组导出在强激光脉冲作用下Ｃｒ＾４＋：ＹＡＧ激发态吸收的恢复时间和饱和光强。实验上在带有抗共振环结构的接近于介稳腔的脉冲式Ｎｄ：ＹＡＧ激光器中用Ｃｒ＾４＋：ＹＡＧ作为可饱和吸收体实现被动锁模运转，得到能量１３．５ｍＪ、平均脉宽１８０ｐｓ的锁模脉冲序列。     

Experimental Study on Flashlamp Pumped Nd3+∶KGd(WO4)2 Laser

The lasing properties of Nd∶KGW crystal in free-running mode with different transmission of the output couplers are reported.The best results have been obtained with the output coupler of 24% transmission.The slope efficiency is 1.0% and the extrapolated energy threshold is 0.54 J.A comparative experiment of Nd∶KGW and Nd∶YAG laser crystals has been cavried out under identical experimental conditions in both free-running and Q-switched modes.The much higher efficiency and the lower threshold for Nd∶KGW (Nd: 2.2 at.-%) compared to Nd∶YAG (Nd: 1.1 at.-%) at 1.064 μm are demonstrated in both operation mode.     

外延单片式激光二极管抽运被动调Q微激光器

基于液相外延工艺,实现了一种结构新颖的单片式被动调Q微片激光器。采用了在激光介质Nd3 ∶YAG表面直接液相外延生长一层具有饱和吸收特性的Cr4 ∶YAG膜的微谐振腔的结构,由于是同质外延生长过程,能够确保饱和吸收体与增益介质间(Nd3 ∶YAG/Cr4 ∶YAG)良好的界面特性。采用光纤耦合激光二极管,在激光二极管输出为1W的抽运条件下,实现了峰值功率近千瓦、稳定重复频率在4kHz以上、脉宽1.8ns、TEM00单横模式、波长1.064μm的调Q脉冲序列输出。在对新型单片式微激光器的性能报道的基础上,阐述了外延单片式结构及其相应工艺的潜在优势。     

千瓦级半导体抽运的固体热容板条激光器

报道了千瓦级激光二极管面阵抽运固体热容激光器的理论与实验研究,分别采用Nd∶YAG单板条和双板条串接的热容激光器,利用热容激光器的理论计算模型计算了在一定的工作时间内激光输出特性,并进行了实验验证。实验中采用的晶体尺寸均为59mm×40mm×4.5mm,对单板条进行抽运时平均功率大约为5.6kW,双板条串接时为11.2kW,重复频率为1kHz,占空比为20%。实验中观察了1s的工作时间内脉冲能量输出的波动情况,单板条时单脉冲能量输出最大为1.3J,在1 s后单脉冲能量输出下降到开始的70%左右,而双板条串接时单脉冲能量输出最大为2.06J,在1s后单脉冲能量输出下降到开始的50%左右,对单块晶体采用通水冷却的准热容热管理模式能有效地降低其热效应。     

多波长半导体激光阵列端泵Nd:YAG脉冲激光器

研制了无温控多波长激光二极管阵列端面泵浦Nd：YAG电光调Q激光器。采用4 000 W多波长准连续激光二极管阵列作为泵浦源,快轴准直镜与透镜导管作为泵浦耦合系统,端面泵浦φ6 mm×60 mm的Nd：YAG晶体,并采用RTP晶体进行电光调Q实验。在重复频率5 Hz、室温（25℃）时,激光器获得了最大输出能量74.4 mJ、脉宽15 ns的1 064 nm脉冲激光输出,光光转换效率达到11%。在25~55℃的工作温度下,对多波长LDA的光谱特征与激光器的输出特性作了测试,激光器输出能量随着工作温度的上升而先迅速下降再逐步保持稳定,当重复频率分别为5 Hz和10 Hz时,激光器对应的最低输出能量分别为48 mJ与37 mJ。     

Experimental Study on Flashlamp Pumped Nd3+:KGd(WO4)2 Laser

The lasing properties of Nd:KGW crystal in free-running mode with different transmission of the output couplers are reported. The best results have been obtained with the output coupler of 24% transmission. The slope efficiency is 1.0% and the extrapolated energy threshold is 0.54 J. A comparative experiment of Nd:KGW and Nd:YAG laser crystals has been cavried out under identical experimental conditions in both free-running and Q-switched modes. The much higher efficiency and the lower threshold for Nd:KGW (Nd: 2.2 at. -%) compared to Nd:YAG (Nd: 1.1 at. -%) at 1.064 μm are demonstrated in both operation mode.     

Properties of Nd：YAG Laser with the Nonlinear Absorption of the Intracavity Fullerenes

ＰｒｏｐｅｒｔｉｅｓｏｆＮｄ：ＹＡＧＬａｓｅｒｗｉｔｈｔｈｅＮｏｎｌｉｎｅａｒＡｂｓｏｒｐｔｉｏｎｏｆｔｈｅＩｎｔｒａｃａｖｉｔｙＦｕｌｌｅｒｅｎｅｓ￥ＬＵＯＴｉｎｇ；ＹＵＺｈｅｎｘｉｎ（ＳｔａｔｅＫｅｙＬａｂｉｒａｔｏｒｙｏｆＵｌｔｒａｆａｓｔＬａ...     

Three-Rod Resonator for Krypton Lamp Pumped 1.8 kW Continuous-Wave Nd：YAG Laser

A three-rod series resonator cw Nd:YAG laser suitable for the industrial applications is presented. The symmetrical resonator laser has been developed and is rated at 1820-W output power with beam parameter product 24 mm.mrad. By utilizing the symmetrical resonator design, the characteristic of beam with multi-rod is not obviously decreased compared with that of a single one. The system total electro-optics efficiency of lamp pumped YAG crystal is as high as 4.0%. The main factors, which affect output power and beam quality of high power solid-state laser module, are theoretically analysed.     

利用位相共轭激光器加工微孔

报道了利用带ＳＦ６气体池受激布里渊散射位相共轭Ｎｄ：ＹＡＧ激光器对０．１ｍｍ厚的刀片进行了微孔加工试验，初步实验结果表明，利用该激光器小的光束发散角这一优点，可加工出出口孔径为２０μｍ微孔。     

LD端面泵浦Cr4:YAG被动调Q激光器输出特性研究

对激光二极管端面泵浦Cr⁴⁺:YAG被动调QNd:YAG激光器输出特性进行了实验研究.实验研究发现,激光器输出功率及脉冲重复频率随谐振腔长度增大而增大.为解释这一实验现象,测量了泵浦光斑在激光晶体内尺寸,同时计算了激光晶体及Cr⁴⁺:YAG晶体内的基模激光光斑半径随谐振腔长度变化.分析结果表明:激光晶体内泵浦光斑尺寸远小于激光晶体内基模光斑半径,腔模间交叠效率较低;当腔长增加时,激光晶体内的基模激光光斑减小,腔模间交叠效率增加,从而导致输出功率及脉冲重复频率随腔长增加而增加;另外,Cr⁴⁺:YAG晶体内光斑半径也随谐振腔长度减小,引起Cr⁴⁺:YAG晶体漂白时间缩短,导致脉冲重复频率随腔长增加而增加.     

High-efficiency flashlamp-pumped Nd:KGW laser

The laser performance of a Nd:KGW rod has been studied in a single flashlamp cavity in the free running as well as in the Q-switched mode of operation at input energies ranging from 1–25J. The results of Nd:KGW have been compared with Nd:YAG operated under identical experimental conditions. The laser extraction efficiency of the Nd:KGW rod was observed to be 2.5 times higher at a much lower threshold than that of the Nd:YAG rod. The intrinsic slope efficiency was determined to be 2.25% and 8.840% for Nd:YAG and Nd:KGW rods, respectively.     

A simple approach to designation of the intracavity resonator for second harmonic Nd:YAG laser

In this paper, the rate equation models, which have been used for describing the high repetitive Q-switched intracavity doubling of Nd:YAG laser, are represented. According to these models and onthe basis of resonator length as the most important parameter for designation of the laser system, a computational procedure (block diagram), which is applied for determination of the doubling intracavity resonator specifications of the Nd:YAG laser, has been provided. According to the resonator length the beam quality inside the resonator for second harmonic generation of Nd:YAG laser in different output powers has been calculated. The results for several green output powers of the laser are compared with the experimental data, and good agreement is obtained.     

660 nm单一波长Nd:YAG陶瓷激光器

 针对陶瓷晶体1319 nm的谱线设计了适合的谐振腔腔镜膜系参量,采用激光二极管列阵侧向抽运掺杂1.1at%、Φ3×50 mm的Nd:YAG陶瓷,利用色散棱镜及KTP晶体Ⅱ类匹配腔内倍频,研制了一台660 nm单一波长输出的高重频Nd:YAG陶瓷红光激光器.根据陶瓷晶体的热透镜焦距设计了谐振腔的各个参量,在重复频率为1000 Hz、单脉冲抽运能量约144 mJ时,获得了3.9 mJ的660 nm脉冲激光输出,总的光-光转换效率为2.71%.为进一步研究大功率、高效率的陶瓷红光激光器奠定了基础.     

Nd~(3+):YAG激光的光纤传输

首先叙述了光纤传输Nd~(3+): YAG激光的优点,接着分析了不同光纤和其传输Nd~(3+): YAG激光的特点。然后通过对光纤传输系统各部分的分析与设计,结合实际,设计了光纤耦合机构。最后,对来自于工件反射光问题提出了解决方案。