就高功率激光二极管阵列端面泵浦大口径放大器提出一种新的耦合方式: 激光二极管阵列拟柱面排布, 即所有激光二极管面阵成1维圆弧型排列, 圆弧的圆心在增益介质的几何中心, 其后紧接一个空心导管进行耦合传输。建立了3维光线追迹程序对这种新耦合方式的特性进行模拟。模拟计算结果表明: 这种耦合方式中二极管阵列排布方式灵活, 当二极管阵列面阵单元以1×12(圆弧方向)、2×6(圆弧方向)、3×4(圆弧方向)这3种排布方式排布时, 在较大的圆半径变化范围内均能实现高的输出耦合效率和高的能量沉积效率; 当增益介质紧贴导管输出放置时, 3种方式排列均能在增益介质中实现均匀平顶分布; 当快轴方向所排阵列个数与慢轴方向所排阵列个数之比接近慢轴发散角与快轴发散角之比时, 能获得更好的耦合效果。

A coupling method is put forward for laser-diode array(LDA) end-pumped amplifiers. The LDA is inscribed on a cylindrical surface and then a duct is connected to it. That means the laser diodes are arranged in the shape of an arch. The center of the arch is at the geometrical center of the gain medium. A three dimensional ray-tracing program is made to simulate the coupling of the cylindrical LDAs. Simulating results show that the cylindrical laser diode array can be arranged flexibly. When laser diode are arranged as 1×12, 2×6 and 3×4 arrays, high coupling coefficient and uniform coupling intensity distribution can be obtained simultaneously when the radius of the arch changes in a wide range; when the gain media is close to the output end of the duct, top-hat deposited pumping intensity distributions can be obtained for the three arrays; when the ratio of the number of laser diodes in the fast axis to that in the slow axis is equal to the ratio of divergence between the fast axis and the slow axis, the best coupling results can be obtained．