【作者】 刘在洲；

【导师】 焦明星；

【作者基本信息】 西安理工大学 ， 测试计量技术及仪器， 2004， 硕士

【摘要】 与传统的灯泵浦相比，激光二极管泵浦固体激光器(DPSSLs)具有高效、长寿命、全固化、热效应和体积小等优点。在众多的DPSSLs中，激光二极管(LD)端面泵浦Nd：YAG激光器在工业中起着重要的作用并得到了广泛的运用，这主要归因于Nd：YAG晶体具有良好的机械和光学特性，而且端面泵浦具有良好的模式匹配，能获得基横模激光输出。 本文首先介绍了LD泵浦Nd：YAG激光器的发展状况、主要特性及其应用，从四能级速率方程出发，推导了LD泵浦Nd：YAG激光器的阈值、输出功率和斜效率的表达式，并简述了激光器的工作原理、结构型式和倍频方法；其次，以空间相关的速率方程为基础，提出了LD端面泵浦Nd：YAG激光器的设计方法，给出了一定泵浦耦合方式下，振荡光模尺寸、最佳输出耦合率、泵浦光模尺寸、泵浦光焦斑位置等参数的选取依据，以此为依据，设计了自聚焦透镜耦合小功率LD泵浦Nd：YAG激光器和透镜组耦合高功率LD泵浦Nd：YAG激光器，对激光器的输出功率和功率稳定性等特性进行了实验研究；再次，在带尾纤输出的高功率LD泵浦Nd：YAG激光腔内插入一只空液晶盒，观察到了激光器以单纵模运转；最后，根据泵浦光焦斑端面位置对激光输出功率的影响规律，提出了LD端面泵浦Nd：YAG激光位移传感新方法，并进行了理论和实验研究，研究结果表明：当激光晶体内泵浦光平均光斑半径远小于振西安理工大学硕士学位论文荡光束腰半径时，激光输出功率的自然指数与泵浦光焦斑的纵向位置成高斯变化规律，测量范围和灵敏度依赖于泵浦功率，随着泵浦功率的增加，测量范围扩大，灵敏度提高，当端面泵浦功率为7.24w(最大输出功率为1.926w)时，激光位移传感器的测量范围和灵敏度分别是13.045mm和0.148mw/pm。更多还原

【Abstract】 Compared with the traditional lamp-pumped solid-state lasers, the diode-pumped solid-state lasers (DPSSLs) have many advantages such as high efficiency, long lifetime, all-solid-state, small size and little heat effect, etc. Of many kinds of DPSSLs, laser diode (LD) end-pumped Nd:YAG laser plays an important role and has been found wide applicatins in industry, mainly because of its good mechanical and optical properties of Nd:YAG crystal and good mode matching to output a fundamental transverse mode.At first, this thesis introduces the progress, main characteristics and applications of LD pumped Nd:YAG laser. In term of the rate equation of Four-energy-level system, the theoretical expressions of threshold, output power, and slope efficiency of the laser has been deduced. The principle of operation and confirgurations of the laser as well as the theory of intracavity frequency doubling are also described briefly. Secondly, a design method for a LD-end-pumped Nd:YAG laser is offered on the base of approach of spatial-dependent rate equation analysis, for a certain pumping configuration, a useful guideline has been given for choosing the parameters including the oscilating laser mode size, transmission of output coupler, the pumping beam size, and the longitudinal position of focus spot of LD pumping beam. According to the guidline, two Nd:YAG lasers have been designed and set up, one is end-pumped by lower output power LD using a selfoc micro lens, and the other isend-pumped by high output power LD using a pair of lenses are designed, and the characteristics such as output power and power stabilization of both solid-state lasers are investigated. Thirdly, when an empty liquid crystal cell is inserted in the cavity of the Nd:YAG laser pumped by high power LD, the laser can operates in single axial mode. Finally, according to the relationship between the laser output power and the longnitudinal a LD-end-pumped Nd:YAG laser sensor for displacement measurement has been investigated theoretically and demonstrated experimently, the results indicate that when the mean radius of pumping inside the laser cavity is far less than that of the oscilating laser mode, the exponential of the output power is a Gauss function of the longitudinal positon of focused spot of LD pumping beam, both the measurement range and the sensitivity are dependent on the incident pumping power, as the incident pumping power is increased, the measurement range is enlarged and the sensitivity is improved. When the pumping power is 7.24W (corresponding to the maximum output power of 1.926 W), the measurement range and the sensitivity are 13. 045mm and 0. 148 mW/ m respectively.更多还原