【作者】 赵致民；

【导师】 侯洵； 白晋涛；

【作者基本信息】 西北大学 ， 光学， 2003， 硕士

【摘要】 本文第一章介绍了全固态绿光激光器的主要特性、优点、应用领域及国内外发展现状。 第二章分析了固体激光器的工作原理，以四能级系统为模型，应用速率方程理论研究了激光场与激光晶体之间相互作用理论，导出了固体激光器的阈值功率、输出功率和斜效率等特性。本章还分析了固体激光领域普遍采用的频率变换技术：建立在耦合波理论上的二次谐波理论，重点分析了相位匹配对转换效率的影响。 第三章分析了激光晶体的热透镜效应，研究了热透镜理论模型和各种测量方法，对这些方法总结、归类并指出了各自的优缺点。 第四章研究了作为泵浦源的光纤耦合输出大功率半导体激光器与激光晶体间的耦合系统。利用矩阵光学的方法，计算了高斯光束经耦合系统聚焦后的像距和束腰宽度，以此为指导设计加工了一套双平凸镜耦合系统，耦合效率达92％；在以上基础上研究了泵浦光与振荡光在激光晶体中的匹配，计算出了泵浦光经耦合系统后的最佳焦点位置。 第五章分析了Nd：YVO₄和LBO晶体的光学特性，深入分析了在引入热透镜效应的情况下谐振腔的像散问题，设计了四镜Z型折叠腔，应用ABCD定律计算优化选择了一组腔参数。LBO晶体Ⅰ类角度相位匹配，Nd：YVO₄和LBO晶体温度分别控制在20℃和18℃，双端总的抽运功率为26W的情况下，获得4.2W的连续绿光输出，光-光转换率为17.6％；LBO晶体Ⅰ类非临界相位匹配（NCPM），Nd：YVO₄和LBO晶体温度分别控制在20℃和148℃，双端总的抽运功率为28.9W的情况下，获得8W的连续绿光输出，光-光转换率为27.7％。进行了总体设计加工，研制出一台样机并通过有关部门鉴定。 最后一章为本论文的总结和建议。更多还原

【Abstract】 In the first chapter of this paper, all-solid-state green laser’s main features and advantages, its field of application as well as the present development at home and abroad are introduced.In the second chapter, the operating principle of solid-state laser is analyzed. Based on the model of four-level system, the interacting theory between laser field and laser crystal is studied by the rate equation theory, then the characters, such as threshold power, output power, slope efficiency etc., of solid-state laser are deduced. The frequency conversion technique applied universally in the field of solid-state laser is studied: the second harmonic wave theory on the base of the coupled wave theory. The effect of phase-matching upon conversion efficiency is mainly analyzed.In the third chapter, the thermal lens effect of laser crystal is studied. The model of thermal lens theory and some measuring methods are explored. These methods are generalized and classified and the advantages and disadvantages of which are pointed out.In the fourth chapter, the coupling system between the fiber-coupled-output high power semiconductor laser acting as the pumping source and laser crystal is studied. By the method of matrix optics, the waist width and imaging distance of Gaussian beams through the coupling system are calculated. By the result of the calculation, a set of double planoconvex lens coupling system are designed and manufactured. The coupling efficiency is up to 92%. On the base of the coupling system, the mode matching between pumping laser and oscillating laser in the laser crystal is researched. The optimum position of focal spot of pumping laser through coupling system is calculated.In the fifth chapter, the optical characteristics of Nd:YVO4 and LBO are studied. The astigmatism problem of resonant cavity is explored thoroughly under the condition of thermal lens effect. Four-lens Z-folded cavity is designed and a set of perfect resonator parameters is screened out by the ABCD theory. With I type anglephase-match of LBO, Nd:YVO4 and LBO are controlled under the temperature of 20 ℃ and 18℃ respectively, and the total double-end pumping power is 26W, a maximum of 4.2W continuous wave green laser can be obtained and the optical-optical conversion efficiency is 17.6%; with I type noncritical-phase-match, Nd:YVO4 and LBO are controlled under the temperature of 20℃ and 148℃ respectively, the total double-end pumping power is 28.9W, a maximum of 8W continuous wave green laser can be obtained and the optical-optical conversion efficiency is 27.7%. We have designed the whole laser system and developed a prototype instrument which was checked and accepted by the department concerned. The final chapter is the summarization and suggestion of the paper.更多还原