针对高功率掺镱双包层光纤激光器(DCFL)的热应力模型,对影响热应力场分布、包层表面最大热应力的参数如:纤芯半径、泵浦方式、泵浦吸收系数进行了研究.结果表明,热破坏作用主要集中于纤芯和包层表面;减小纤芯半径或增加光纤长度能够降低包层表面的最大热应力值;双端对称泵浦较之其它泵浦方式性能更优;采用非均匀泵浦吸收系数方案在降低包层表面最大热应力的同时,维持了高功率输出.
Aim at the model of Yb - doped double - clad fiber lasers (DCFL), the parameter impacting the maximum thermal stress of clad surface such as radius of core,pump fashion,pump absorption coefficients are studied. Results indicate that serious problems such as fracture are caused around core and clad surface of the laser. Increasing the core radius and fiber length can reduce the maximun thermal stress of clad surface. The two end syrmnetrical pump fashion is more superiority than other pump fashion. So an approach with nonuniform pump absorption coefficients is proposed to reach the reduction of the maximum thermal stress of clad surface and high output power.