对线形腔LD泵浦掺镱的双包层光纤激光器进行研究，通过数值模拟，分析了不同泵浦方式下的泵浦光、激光输出功率和增益特性在光纤中的分布。结果表明，单端后向泵浦输出功率率较高，对于小功率光纤激光器则是最佳选择。进一步又研究了单端后向对称泵浦输出功率与光纤长度及腔镜反射率的影响，为提高光纤激光器的输出功率提供了理论和实验依据。

The output characteristics of LD-pumped Yb³⁺-doped double-clad fiber lasers with linear cavity are studied.By means of numerical analysis,the distribution of pump light,laser power and the gain character along the fiber with different pump modes has been researched on. The results show that end-back-pumped is the optimum for low power fiber lasers. And the further research is conducted on the relation of output power with pump power,as well as the effects of fiber length and cavity reflectivity on output power. It will be helpful for improving the power of fiber lasers in theories and experiments.