光束合成是研制高功率、高光束质量固体激光器的必由途径。建立板条介质固体激光器阵列光束合成的理论模型,从子束间距、整体相位差、偏振态、随机像差等方面,分析了合成光束的远场特性。通过数值模拟可以看到,子束间距决定了合成光束远场光斑的衍射旁瓣的大小和多少;子束间整体相位差决定着合成光束远场中心光斑是否分离,并影响着峰值光强和x方向半径大小;偏振态差异决定了合成光束是否为相干合成或强度叠加;子束随机像差降低了合成光束的远场光斑峰值功率,并引起光束的弥散。分析结论对激光器研制中合理分配设计容差具有一定指导意义。

Beams combination is the only way for development of high power and high beam quality solid state lasers. Applying mathematical model of array combination for slab laser, it is simulated on the computer that intensity distribution of combined far-field spots changes with some factors, such as interval, integer phase difference (also called piston aberration), polarization and random aberration of array beams, and some useful results are obtained. The interval of two beams decides the energy and number of diffraction ring. The integer phase difference between two beams imposes on whether separation of their far-field spots, and affects its peak intensity and x direction radius. The polarization difference decides whether coherent combination or incoherent combination. The random aberration of each beam reduces peak intensity of their far-field combination spot, and makes it dispersion. These results are useful for designing beam combination of slab laser.