【作者】 赵海川；

【导师】 许晓军；

【作者基本信息】 国防科学技术大学 ， 光学工程， 2008， 硕士

【摘要】 激光介质的热效应对激光的光束质量有着严重的影响,板条激光介质可以利用Zig-Zag光路周期性穿越温度梯度方向以减小热聚焦及应力双折射效应。采用端面泵浦和传导冷却技术,板条激光器可以得到良好的光束质量和高平均输出功率,这些优点使其倍受关注,在工业和军事中有着重要应用前景。论文在概述板条激光器的发展,重点介绍传导冷却端面泵浦板条(Conduction-Cooled End-Pumped Slab,CCEPS)激光器的发展及其进展情况的基础上,对基于CCEPS模块的多角度激光/放大器进行了研究。首先,运用几何光学的方法,对影响板条介质填充因子的各因素进行分析,讨论了各因素对填充因子的影响;建立了CCEPS的几何光学仿真模型,模拟了板条介质对入射光束角度的敏感性,分析了激光器中杂散光的形成原因。进一步研究了多程放大理论,计算了不同种子功率条件下,填充因子对输出功率的影响;论证了多角度放大的可行性,对其中存在的问题进行了讨论并确定了四程放大光路具体方案。开展了实验研究,实验了不同谐振腔型的CCEPS激光器,获得了最大功率142W的激光输出,光-光效率33%;实现了基于CCEPS多角度放大单程,双程以及四程放大光路,在小信号时得到十倍以上的放大输出;对实验提出了进一步改进方案。更多还原

【Abstract】 The influence of thermal effect of the laser gain medium on the laser beam quality is serious. Slab laser gain medium eliminates thermal gradient induced lensing in the thickness direction and minimizes stress gradient induced birefringence when the ray propagates in a Zig-Zag manner. With End-Pumped and Conduction-Cooled technology,slab laser could produce high-average-power with good beam quality which makes it have developed rapidly and has a extensive application value in many fields.By summarizing the development of slab laser,especially the development of Conduction-Cooled End-Pumped Slab (CCEPS)laser, geometrical optics analysis of CCEPS laser/amplifer and angularly multiplexed amplifer are studied. First, using geometrical optics method,we analyse the factors which affect the fill factor and discuss the influence of each factor;found the model of CCEPS and simulate the sensitivity of angle to the slab;analyse the cause of stray light .And then,study the theory of angularly multiplexed amplifer,compute the fill factor’s influence on output power when the input power is different,discuss and confirm a four pass angularly multiplexed amplifer optical path.Last,we did some experiments based on CCEPS. The max output power of power oscillator is 142W with an optical to optical effiency of 33%.Experiment one pass,two pass and four pass master oscillator-power amplifier,realizing angularly multiplexed amplifer based on CCEPS which produce a decuple output power in small signal;Advance some suggestions for next step experiments.更多还原