腔型结构对LD端面泵浦Nd:YAG激光器输出特性的影响

在腔长为 2 47mm的LD端面泵浦Nd :YAG激光器的谐振腔中加入一片凸透镜 ,改变腔型结构 ,发现输出功率由 0 .3 5W增至 1.19W ,M2 因子由 1.0 9增至 2 .6,阈值功率由 2 .78W降至 0 .68W ,与腔长为 2 0mm的谐振腔阈值功率相同。分析表明 ,由于透镜的变换作用 ,使得泵浦端面上振荡光斑与泵浦光斑的比例发生变化 ,在晶体后端面处泵浦光斑确定的情况下 ,激光器的输出功率和阈值功率主要取决于该处的振荡光斑大小 ,与有效模体积无直接关系

The effect of the resonance structure on the output beam characteristics in LD end-pumped Nd:YAG lasers

When a convex lens was placed into the 247mm-long resonator of a LD end-pumped Nd:YAG laser,the resonance structure was altered,and the power output increased by a factor of 3.4,while the M 2 factor was a little bigger than before,changed from 1.06 to 2.01,meantime the threshold pumping power decreased from 2.78W to 0.68W.Analysis indicated that the power output and the threshold pumping power was mainly determined by the radius of oscillating beam in the pumping end of the laser crystal when the radius of pumping beam was given in the same face,the effective mode volume had little effect in this conditions,and characteristics of the output beam and the oscillating beam can be controlled by changing the position of the convex lens.