理论推导了相干光束阵列远场光强分布的解析表达式.介绍了填充因子及五种相干合成效果评价参数的定义.分析了填充因子对远场光强分布的影响,发现填充因子通过影响空间调制因子来改变远场光强分布.求得了相干合成效果评价参数与填充因子的关系式,并绘制了关系曲线.计算结果表明,斯特列尔比与填充因子无关,恒为1;中央主瓣半径与填充因子成正比关系;中央主瓣能量密度受填充因子的影响较小;中央主瓣能量比与填充因子的平方成近似正比关系;桶中功率与填充因子的关系很复杂,但总体上随着填充因子的减小而减小.分析显示,若要保证中央主瓣能量比和PIB值均大于最佳值的一半,则填充因子应大于√2/2.
Theoretical analysis on the far-field diffraction of the coherent beam combination (CBC) is presented. An intro-duction is given to the definitions of filling factor and evaluation parameter of CBC. Based on the theoretical mode and definition, the influence of filling factor on far-field intensity distribution and the relationship between evaluation param-eter and filling factor are theoretically described in detail. It is found that the filling factor influences far-field intensity distribution through space modulation factor. Results also indicate that SR is a constant which has not connection with the filling factor, and CR is of a linear relation with filling factor, and NACL has little connections with filling factor, and RCL varies approximately linearly with the square of filling factor, and PIB decreases when filling factor increases in general. If we make the filling factor larger than √2/2, more than half of the best values of RCL and PIB may be obtained.