利用Wigner分布函数,对复杂像散高斯光束的并合问题进行了详细研究,得到了相干和非相干并合光束的光强分布和M2因子的解析表达式.解析结果和数值计算均表明,并合光束的特性与子光束数目、相对间距和几何排布等因素有关.以光束传输因子(M2)作为标准时,相干并合光束质量优于非相干并合;以桶中功率(PIB)作为标准时,相干并合光束质量并不总优于非相干并合.

By using Wigner distribution function, the beam combination characteristics of general astigmatic Gaussian beams are studied. The analytical formulas of intensity profiles and beam propagation factor (M2) for incoherent and coherent combinations are derived. The analytical and numerical results show that the beam quality of the resulting beam depends on the number, normalized separation distance and geometrical arrangement of beamlets. The beam quality of the coherent combination is better than that of the incoherent combination when the beam propagation factor (M2) is chosen as the criterion, whereas the beam quality of the coherent combination is not always better than that of the incoherent combination, if the power in the bucket (PIB) is adopted as the criterion.