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1.
 测量了高强度三倍频实验的1ω 光和3ω 光的近场光束质量,将测量和模拟计算所得到3ω 光近场光束质量作了对比,重点对模拟计算得到的3ω 光近场光束质量所存在的误差进行了探讨,分析了现有的模拟计算程序中还未考虑到的影响3ω 光光束质量的主要因素,建议在以后的模拟计算程序中再进行优化设计,并讨论了改善3ω 光光束质量应采取的必要措施。  相似文献   

2.
 建立了光束质量控制的数学模型,提出了一种可定量评价光束质量的参数优化选择方法。针对激光测头进行了两片式光束质量控制光学系统的优化设计,并与光束聚焦控制、准直控制方法进行对比实验。激光结果证明:该优化光束控制系统在测量范围内既保持了光束的均匀性,光斑尺寸较小(光腰尺寸为34 μm),又保证了光束的精细度,有效地抑制了光束质量引入的测量误差,在±5 mm测量范围内,其均方根误差仅为6.3 μm,测量精度明显优于聚焦控制和准直控制系统。  相似文献   

3.
抽运光波前畸变对拍瓦激光器前端OPA光束质量的影响   总被引:1,自引:0,他引:1  
数值模拟了拍瓦激光器前端非共线光参变放大(OPA)过程中存在波前畸变的抽运光对信号光光束质量的影响.结果表明,当抽运光光束波前存在严重畸变时,衍射效应和走离效应通过不同的物理机制导致了信号光光束质量的急剧下降.在导致信号光光束质量下降的过程中,走离效应在OPA未饱和放大时起着主导作用,当OPA工作在过饱和状态时,过饱和导致的信号光近场空间分布中心凹陷成为光束质量下降的主要因素.  相似文献   

4.
为便于评价两种光场空间分布之间的偏离程度,引入一个数学参数δ进行研究。将该参数应用到谐振腔内分析了抽运光空间分布对基模振荡光光束质量的影响。这种影响主要表现为:若抽运光在激光介质中引起非均匀的增益分布,基模振荡光将偏离高斯分布。利用δ参数对这种影响的程度进行了定量估算。定量研究表明:δ参数可以直观地反映泵浦光分布对激光器光束质量的影响程度,而且在激光器的设计中δ参数的大小可衡量泵浦光分布的优劣。对于端面泵浦二极管泵浦固体激光器(DPL),稳恒运转下最理想的抽运光分布形式是高斯型抽运光,其半径等于谐振腔的基模高斯振荡光半径。  相似文献   

5.
泵浦光束质量对受激拉曼散射的影响   总被引:3,自引:3,他引:0  
楼祺洪  宁东 《光学学报》1998,18(8):020-1024
主要讨论泵浦光束质量对低气压拉曼种子源特性的影响。文中给出了一阶斯托克斯光泵浦阈值、输出能量和光束质量的实验数据。用M^2因子分析了泵浦光和一阶斯托克斯光的光束质量。根据考虑泵浦聚焦和泵浦光束质量影响的近似拉曼散射理论计算了泵浦阈值的理论曲线,并与实验数据和有关文献进行了比较。  相似文献   

6.
开展了双光束中红外光学参量振荡器(OPO)的偏振合成实验研究,数值分析讨论了偏振合成过程中单元光束束腰半径和系统低阶像差对合成光光束质量的影响。在此基础上,最终实现了10 W3.78μm中红外激光的稳定输出。与此同时,利用刀口法对偏振合成前后单元光束及合成光束的光束质量分别进行了测量。结果表明:合成光光束质量达到1.2。  相似文献   

7.
三倍频光学系统中近场调制增长规律研究   总被引:2,自引:0,他引:2  
高功率固体激光装置的光束质量控制既要满足精密物理实验的苛刻要求,又要保证激光装置在高负载条件下的安全运行,是建造激光器的核心环节。三倍频光学系统承担着将1.053 μm的基频光转换成0.351 μm的三倍频光并聚焦到靶上的任务,是影响激光装置光束质量的重要环节。基于B-T理论研究了非线性传输条件下三倍频光学系统中光束调制的增长规律,基于典型的KDP晶体面形数据建立的中高频相位屏模型,通过数值计算获得了三倍频光学系统不同B积分下光束近场的变化规律。研究表明,三倍频光学系统中最快增长频率和相应的最快增长因子都是为基频光系统的三倍,空间调制周期在0.1~1 mm之间的空间频率成分增长最快。当三倍频光学系统B积分的设计值为1.5,要求三倍频光近场调制度小于1.15时,中高频噪声的RMS值必须控制在1.6 nm以下。  相似文献   

8.
完美涡旋(POV)光束具有光束半径与拓扑荷数无关的特点,与其他涡旋光束相比具有更加稳定的空间强度分布特性。利用多相位屏法和傅里叶变换法,分析了POV光束在大气湍流中的斜程传输特性。采用光束漂移和孔径平均闪烁指数作为大气湍流影响光束质量的评价参数,对比了POV光束与高斯涡旋光束在相同传输条件下的光束质量。结果表明:相比于高斯涡旋光束,POV光束的光束稳定性更好。当拓扑荷数增大或天顶角减小时,POV光束抵抗大气湍流的能力增强。在不改变POV光束拓扑荷数的前提下增大其光束半径,也能提高POV光束对大气湍流的抵抗能力。  相似文献   

9.
基于砷酸钛氧钾(KTA)晶体优良的非线性光学特性,研究了由1μm Nd:YAG纳秒脉冲调Q激光器泵浦的高能量、高光束质量闲频光单谐振光参量振荡器。选取合适镀膜参数的腔镜、优化腔型设计,建立了一个稳定紧凑的半球形对称闲频光单谐振腔,实现了高能量、高光束质量的近-中红外激光输出。在输入泵浦光的(1.064μm)最大能量为20.2 mJ时,输出信号光(1.535μm)和闲频光(3.468μm)的最大能量分别为2.91 mJ和1.13 mJ,对应信号光和闲频光的斜效率分别为20.9%和8.1%。闲频光单谐振的光参量振荡器具有更大的衍射损耗和光束发散角,可以极大的限制输出光束的光谱带宽、提高谐振闲频光的光束质量等优势,测量了输出中红外闲频光在两个正交方向上的光束质量因子分别为Mx2≈1.1,My2≈1.1。  相似文献   

10.
应用液晶空间光调制器加载螺旋相位片的方法可以高效地生成涡旋光束,但由于液晶空间光调制器分辨率有限,在加载高阶螺旋相位片时其中心会出现相位失真,造成涡旋光束质量不高。通过在螺线相位片中心区域引入闪耀光栅的方法,得到了光束质量较高的高阶单模涡旋光束和多模涡旋光束,为生成高阶涡旋光束提供了一种很好的方法。  相似文献   

11.
韩开  吴双  张彬 《强激光与粒子束》2013,25(5):1134-1138
利用有限元分析法结合Fox-Li迭代法,考虑腔内本征模式与腔镜热形变的相互耦合作用,计算模拟了正支共焦非稳腔的本征模式分布,定量分析了高功率激光器腔镜热变形对输出光束质量的影响,重点讨论了腔镜热变形所引起的腔内本征模式相位特性的变化,并从波前功率谱密度、Zernike像差系数及光束质量值等角度对腔镜发生热形变前后的激光器输出光束的光束特性进行比较分析。研究结果表明:高功率激光器腔镜热形变对输出光束的光束质量会产生一定的影响,且随着激光输出功率的增大,镜面热形变引起的输出光束波前相位高频比例及Zernike高阶像差均会有所增大,波前畸变程度也明显变大,光束质量逐渐变差。  相似文献   

12.
Yan Zhang  Bin Zhang 《Optik》2010,121(13):1236-1242
The beam quality of the laser beams after spectral beam combining (SBC) has been analyzed in this paper. Based on the propagation model of the spectral beam combining system, the expression for the output field of an individual beam passing through the spectral beam combining system with lens aberration has been given and the intensity distribution of the combined beam has been studied by the principle of incoherent superposition. Consequently, according to the intensity second-order moments method, the M2-factor of the combined beam has been calculated and the effect of lens aberration on the characteristics of the combined beam has been analyzed quantitatively. It can be shown that the SBC system can improve the beam quality of laser array significantly, and the M2-factor of the combined beam passing through the ideal spectral beam combining system is almost the same as that of an individual beam. For the spectral beam combining system with lens aberration, the spherical aberration has greater effect on the off-axis beam than on the on-axis beam, and the beam quality of combined beam degrades with increase in lens aberration.  相似文献   

13.
Fuxing Fu 《Optics Communications》2011,284(19):4563-4569
By constructing a distorted wavefront with random phase screen, the correction process of distorted wavefront has been simulated, and the correction effect of deformable mirror has been simulated and analyzed with the method of high-pass filtering. The variations of correction effect and high-frequency phase distortion have been quantitatively analyzed. The results show that the beam quality of the corrected beam degrades obviously with the increase of high-frequency phase. In addition, a new method has been presented to recover the high-frequency phase of distorted wavefront according to the given intensity distribution and low-frequency phase in near field and the intensity distribution in far field. It shows that the method is very effective to recover the high-frequency phase of distorted wavefront.  相似文献   

14.
高能激光器气动窗口光束质量的评价方法探讨   总被引:4,自引:2,他引:2       下载免费PDF全文
 通过对高能激光器气动窗口的研究现状和应用需求的分析,指出建立一套气动窗口光束质量的评价方法是十分必要的。在分析气动窗口工作机理和现有激光光束质量评价因子的基础上,提出一种评价气动窗口光束质量的方法,即用斯特列尔比来评价气动窗口的光束质量,并辅以相对衍射极限因子进行远场直观说明。分析表明,此种评价方法是可行的,并达到了不受限于气动窗口类别的光束质量评价的要求。  相似文献   

15.
Beam quality considerations of high power Nd:YAG lasers   总被引:1,自引:0,他引:1  
High power Nd:YAG lasers with fiber optic beam delivery have introduced new capabilities for material processing applications. Here, we present the stable resonator design for high power Nd:YAG lasers to optimize beam quality for fiber optic transmission. Dependence of beam parameters on position and dioptric power of thermal lens has been investigated and optimized to achieve efficient fiber optic beam delivery. With the optimum resonator configuration, an efficient fiber optic beam delivery over the entire operating range of input power has been achieved. The results of stable resonator design with good beam quality and output power have been presented.  相似文献   

16.
报道了一种利用球差补偿效应提高侧面泵浦主振荡功率放大器输出光束质量的实验装置。在理论上提出了一种新的球差补偿方法,利用正球差经过会聚透镜焦点后向负球差转化的现象,补偿下一放大级中的正球差效应。在实验上搭建了两级放大的侧面泵浦Nd:YAG主振荡功率放大器。在连续输出的情况下,从振荡级输出功率为42W、光束质量因子为1.48的种子光,经过一级放大后的功率为74W,光束质量因子恶化为1.80;继续经过二级放大后,光束质量因子提高为1.40。实验结果表明,所提出的球差补偿理论是提高激光放大过程中光束质量的有效手段。  相似文献   

17.
The propagation model for the spectral beam combining system of five Yb-doped fiber laser beams by the volume Bragg gratings (VBGs) has been built up. Considering the surface distortion by thermal effect, the intensity of an individual beam passing through the spectral beam combining system by the VBGs with deformation has been analyzed numerically and iteratively by using finite-different and sparse matrix methods, and the intensity of combined beam has been studied by the principle of incoherent superposition. Consequently, according to the intensity second-order moments method, the M2-factor of the combined beam has been calculated. The effects of deformation of the VBGs on the intensity, the combining efficiency, the M2-factor and the power in the bucket of the combined beam have been analyzed quantitatively. It can be shown that the effects of the deformation of the VBGs on the intensity distribution of combined beam become more and more obvious with the increasing of the deformation of the VBGs. The results show that the surface distortion of the VBGs due to high-power lasers dramatically degrades both the beam quality of the combined beam and the combining efficiency of the spectral beam combining system.  相似文献   

18.
高功率二极管泵浦腔内倍频激光器   总被引:8,自引:4,他引:4       下载免费PDF全文
 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。  相似文献   

19.
为了分析组束激光的战术应用前景,对强激光大气传输的远场光束亮度进行了理论分析和数值模拟。结果表明:10kW量级的强激光有效作用距离不超过10km,需要对发射系统孔径和光束质量进行严格的控制;激光器承载平台的抖动幅度是影响远场光束功率密度的主要因素,在抖动幅度很小或者可以忽略的条件下,湍流和热晕对远场光束起着近乎相同的作用。  相似文献   

20.
A high efficiency and high peak power laser system with short-pulse and good beam quality has been demonstrated by using a master oscillator power amplifier with two-pass amplification configuration. The master oscillator, end-pumped with a fiber-coupled laser diode array, provides low power but excellent beam quality pulses, and the amplifier boosts the pulse energy by orders without significant beam quality degradation. Short pulses of 8.5 ns with energy up to 130 mJ and approximately diffraction limited beam quality have been demonstrated.  相似文献   

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