不同抽运结构DPL增益分布及输出特性的研究

发布时间：2018-02-26 19:03

本文关键词： 二极管抽运固体激光器侧面抽运端面抽运增益分布　出处：《西安工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：二极管激光器抽运的全固态激光器(DPL)具有全固态、体积小、使用寿命长、抽运效率高等诸多优点,使得其在激光通讯、遥感探测、医疗、工业、军事和国防等领域具有广泛的应用领域和前景,因而受到了研究者极大的关注。本论文对不同抽运结构的DPL增益分布和激光器的输出特性进行了研究,分析了不同抽运条件下抽运光和抽运结构的特点,采用数值计算方法,计算了不同抽运条件下抽运光参数对激光工作晶体中的增益分布的影响；计算结果表明,抽运光束腰半径越小,激光晶体的轴线上增益越大,垂直于轴线方向的径向增益分布越集中；晶体的吸收系数越小,抽运均匀性就越好,但总的吸收效率下降；在吸收系数和束腰半径过小时,晶体不能完全吸收抽运光的能量,抽运光利用率降低；此时在晶体侧面抽运光出射面增镀抽运光的增反射膜,能提高抽运光的能量利用效率。进而数值计算了不同抽运光束腰大小、束腰位置对激光器输出特性的影响。给出抽运光束腰半径越小,激光器输出特性越好。特别是对端面抽运结构,存在一个最佳的抽运光束腰位置,使得激光器的输出特性最好。最后通过端面抽运结构,实验研究了光纤耦合LD的输出功率特性和光谱特性,并进一步通过实验比较研究了端面离轴抽运激光器的输出功率和输出光束质量。
[Abstract]:Diode-pumped all-solid-state lasers (DPLs) have many advantages, such as all-solid-state, small size, long service life, high pumping efficiency and so on, which make them widely used in laser communication, remote sensing, medical treatment, industry, etc. Military and national defense have a wide range of applications and prospects, which has attracted great attention of researchers. In this paper, the gain distribution of DPL with different pumping structures and the output characteristics of lasers are studied. The characteristics of pumping light and pumping structure under different pump conditions are analyzed. The influence of pump light parameters on the gain distribution in laser operating crystals is calculated by numerical calculation method. The smaller the beam waist radius, the greater the gain on the axis of the laser crystal, the more concentrated the radial gain distribution perpendicular to the axis, the smaller the absorption coefficient of the crystal, the better the pumping uniformity, but the lower the overall absorption efficiency. When the absorption coefficient and the beam waist radius are too small, the crystal can not completely absorb the energy of the pumped light, and the utilization ratio of the pump light decreases. The effect of different pump waist size and beam waist position on laser output characteristics is numerically calculated. The smaller the beam waist radius is, the smaller the beam waist radius is. The better the output characteristics of the laser, especially for the end pumped structure, there is an optimal pump beam waist position, so that the output characteristics of the laser is the best. The output power and spectral characteristics of fiber coupled LD are experimentally studied, and the output power and output beam quality of the end-face off-axis pumped laser are compared.
【学位授予单位】：西安工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN248.1

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