建立了矩形阵列高斯光束合成模型,采用数值模拟方法计算了光束间距、单元光束特性以及阵列结构等参数对非相干合成和同相位相干合成的远场峰值强度及光束质量的影响,描述了非同相位相干合成可能产生的结果,讨论了同轴与非同轴合成,相干与非相干合成的特点。结果表明:非相干和同相位相干合成时的光束质量随着单元光束的增多而变差,并且随着光束间距与单元光束束腰之比的增大而下降;而非同相位相干合成的结果较为复杂,可能产生完全相消干涉,合成光束“重心”离轴及束腰位置偏移等现象。分析认为:同轴合成可以获得最佳的光束质量,是值得采用的合成方式。此外,同轴相干合成优于非相干合成的充分条件是将单元光束之间的相位差控制在(-π/4,π/4)以内。

A Gaussian beam combination model of rectangular array was established. By numerical analysis method,influences of beam separation distance,characteristics of unit beam and array structure on far field peak intensity and beam quality of incoherent combination and the same phase coherent combination were researched. Some results generated by the different phase coherent combination were described,and the features of coaxial combination,non-coaxial combination,incoherent and coherent combination were discussed. The results show that beam quality of incoherent combination and the same phase coherent combination deteriorate with the increase of the unit beam number as well as the ratio of beam separation distance to unit beam waist. For the different phase coherent combination there are some results such as complete destructive interference,off-axis of spreading center and shift of beam waist plane. It is found that coaxial combination is a worthy method of beam combination for obtaining the best beam quality. Moreover,a sufficient condition in which coaxial coherent combination is better than incoherent combination is that phase differences among all beams should be within (-π/4,π/4).