理论上分析了基于布里渊放大的非共线组束结构中组束效率的影响因素,结果表明,当Stokes种子光和抽运光的夹角限制在90 mrad范围内时,组束效率可以达到80%以上.根据数值模拟的结果,设计了非共线四束激光组束的实验,实现了四束工作频率为10 Hz,能量分别为70.4 mJ,71.3 mJ,78.9 mJ,70.1 mJ的激光组束,组束输出能量为189 mJ.为了进一步简化结构和降低系统损耗,设计了适用于多束激光非共线组束的介质池结构.
A non-collinear laser beam combination based on Brillouin amplification was proposed. The influence of non-collinear Brillouin amplification on the combination efficiency was analyzed and discussed theoretically. It was shown that the efficiency of 80 % can be achieved with the angle between the Stokes and the pump limited in the range of 90 mrad. According to the theoretical results, a four-beam non-collinear combination experiment was designed and carried out. The output energy of 189 mJ at 10 Hz was achieved with the energies of the four pumps being 70.4, 71.3 , 78.9 and 70.1 mJ, respectively. In order to simplify the scheme and reduce the optical loss, a construction of SBS cell for non-collinear combination of multiple beams was also designed.