共查询到19条相似文献,搜索用时 62 毫秒
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固体激光器是一种具有重要应用背景的高功率激光器,对包括激光波长、光束发射口径、发射功率、光束质量等在内的激光器参数的选择进行了分析,研究了大气介质的光学性质、激光大气传输效应以及激光辐射与靶目标的耦合机制与耦合效率等因素的影响.相关结果表明100 kW的固体激光器的综合效能可与2~3倍平均输出功率的DF化学激光器相当,这说明高平均功率固体激光器是一种具有潜在优势和良好发展前景的高功率激光器. 相似文献
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从激光推进的要求出发,阐述了用于激光推进的高功率激光器的选择原则,即激光器必须满足:(1)高的平均功率和峰值功率;(2)高的单脉冲能量;(3)高的重复频率;(4)优良的大气传输特性。主要分析了目前YAG固体激光器、自由电子激光器和TEA脉冲CO2激光器的特点,通过上述4个方面性能的比较,认为在目前水平下,TEA脉冲CO2激光器是进行激光推进的首选强激光源,其优点表现在:功率可达10kW量级,单脉冲能量可达0.5~1kJ,重复频率为20~40Hz;激光波长处于大气传输窗口,对大气变化不敏感;工作物质快速流动,不存在热透镜效应和破坏阈值;相关光学元件易于制造;光束质量较好;运行成本低。 相似文献
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中红外激光在通信、遥感、安检和光电对抗等许多领域中都有重要的应用价值,一直以来都是激光领域研究的热点。中红外激光的产生方法有很多,其中光纤中红外激光器具有结构紧凑、光束质量好和转换效率高等特点,故被认为最有希望实现便携、稳定、高效和高功率的中红外激光输出。随着软玻璃光纤制备工艺水平的提升,中红外光纤激光技术获得了快速发展,输出功率水平也得到了很大提升。然而,受限于稀土离子种类、软玻璃光纤制备工艺和软玻璃光纤化学稳定性,基于软玻璃光纤的中红外激光器在功率进一步提升和波长拓展方面存在技术瓶颈,近年出现的中红外光纤气体激光器为此提供了有效的解决方案。详细综述了中红外光纤激光技术的研究现状,包括基于气体填充空芯光纤的新型中红外光纤激光器,并简要展望了中红外光纤激光技术的发展趋势。 相似文献
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激光的本质是微观粒子的有序运动,而热是微观粒子的无序运动,高能激光产生过程中这一对矛盾贯穿始终,可以说高能激光的发展史,就是一部与废热的斗争史。回顾高能激光发展的六十年,剖析高能激光的科学内涵,我们大致将其划分为前后三十年的两个阶段,前一阶段着重解决能用的问题,后一阶段重在解决好用的问题。围绕产热、散热,我们剖析了激光功率、光束质量、效率三者之间的内在关联,简要回顾了各类高能激光器的发展历程,评价了各类高能激光的特色,展望了高能激光未来的发展路径。 相似文献
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概述国外激光战术武器的发展现状,并对其在现代战争中造成的威胁以及激光战术武器的关键技术进行了评述。 相似文献
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A generalised ABCD matrix treatment for laser resonators and beam propagation is developed for computer programming. In this treatment, imaginary parts are introduced into the matrixes for all optical elements, and the beam quality factor M2 and the index of the medium are also taken into account. When the imaginary parts of the complex matrix are zero and the beam quality factor M2 and medium index are unity, the stated method is transformed back into the more classic ABCD matrix format in which the fundamental-mode Gaussian beam transmits through real elements in the vacuum. Based on this method, laser resonator software is realised by the VB programme language. The software can be used to analyse and design stable/unstable standing/travelling cavities, phase-conjugate cavities and beam transformations. 相似文献
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The two-dimensional Laplace integral transform technique has been applied to get the spatial and temporal temperature distributions in both the molten layer thickness of a thin film coated on a substrate, the still solid part of the thin film of the target and the temperature distribution in the substrate. Also a formula for the time dependence of the evaporated part of the thin film of the target as well as the molten layer thickness of the thin film were obtained. Calculations of the obtained relations were carried out during the irradiation with a pulsed laser. The derivation has taken into account the temperature-dependent absorption coefficient of the irradiated surface and the chemical reaction in the vapor of the thin film. As an illustrative example, computations were carried out on an aluminum thin film coated on a glass substrate. 相似文献
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S. E. -S. Abd El-Ghany 《Optics & Laser Technology》2001,33(8):539-551
The two-dimensional Laplace integral transform technique has been used to compute the temperature profile of the molten layer on the surface of a semi-infinite target when irradiated by a pulsed laser. Mathematical expressions for the temperature distribution in the molten layer thickness and the solid part of the target, taking cooling and the temperature-dependent absorption coefficient of the irradiated surface into account, were obtained. As an illustrative example computations were carried out on a semi-infinite aluminum (Al) target. 相似文献
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Abstract Of the new laser dyes of coumarin series reported earlier, pyrazolo derivatives have been further studied. The paper reports their laser spectra and efficiencies in various solvents compared to a standard coumarin laser dye C515. One of the derivatives shows comparable output under optimum concentration conditions as compared to the standard. 相似文献
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为了获得高质量小孔,克服单脉冲激光打孔的不足,设计了一种能够产生多脉冲激光波形的激光器电源.并在1mm厚的薄钢片上得到直径小于1mm的小孔.多脉冲打孔理论分析表明,多脉冲激光打孔不但减少了熔融物和等离子体的产生,而且降低了激光打孔对高能量的要求,获得的小孔质量优于单脉冲激光打孔.另外脉冲宽度和脉冲间距的选择对激光小孔加工质量起决定性作用,在加工高质量孔的时候,应该选用较短的激光脉冲宽度.实验表明,利用三脉冲激光输出波形打孔所获得的小孔质量要优于单脉冲激光打孔效果,有效脉冲平均能量为350mJ,宽度为100μs,脉冲间距为100μs. 相似文献
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A novel model of beam formed by coherent superposition of two correlated Gaussian spherical beams with different centers is presented. This kind of beam has a transverse spreading smaller than a fundamental Gaussian beam. The beam quality factor is smaller than one. 相似文献
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A new approach to eye-safety analysis for airborne laser systems flight test and training operations
A new method for evaluating the hazards associated with the use of airborne laser systems operating in the visible and near infra-red portions of the electromagnetic spectrum is presented in this paper. Particularly, safety issues of state-of-the-art Nd:YAG laser target designators are thoroughly investigated, in order to identify operational procedures and limitations for employment of such equipment at the test ranges during execution of both trials and training missions. Innovative procedures and algorithms are presented that allow a complete verification of laser-safety for airborne systems whilst operating at the test ranges. Finally, a PC based simulation program is described, together with some simulation results.Most of the results presented here have been developed for airborne laser target designators, but they also apply to most airborne laser systems including range finders and beam riders operating in the visible and near-infrared portions of the electromagnetic spectrum. 相似文献
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分析了角锥棱镜对光束的相位变换作用,带二面角误差的角锥棱镜可等效于6块光楔的组合,其楔角的大小和方向由二面角误差决定。对在腔内往返传输的光线在镜面上的位置进行了分析,结果表明:3个二面角误差相同且不为零的角锥棱镜构成的谐振腔为约束非稳腔。用Fox-Li迭代法数值模拟得到了不同棱镜二面角误差情况下的谐振模式。模拟结果表明:圆形镜腔情况下基本振荡模式接近于TEM03模的拉盖尔高斯光束;当3个二面角误差不相同时,模式中各个区域的强度分布不对称。采用3个二面角误差基本接近且绝对值较小的棱镜可以提高光束质量。 相似文献