为了克服大口径激光系统目前面临的困难, 提出使用多束中小口径激光在靶面实现能量叠加的方式。为满足靶面辐照均匀性与对称性的要求, 对多束激光的同步控制精度及脉宽控制精度对叠加光束的影响进行分析。研究表明, 多脉冲辐照的同步性会影响靶面中心辐照的能量分布。当单束脉冲延时大于等于两倍脉宽时, 靶面中心光强峰值将降至75%, 两束脉冲延时大于等于两倍脉宽时, 靶面中心光强峰值将降至50%。当一个光束的脉宽增加到其他参与叠加的光束的两倍时, 靶面中心光强峰值将降至理想叠加情况的87.5%。

In order to overcome the difficulties of the large aperture laser system, combining the output energy of multiple laser beams with small aperture at the target surface was a feasible scheme. To meet the target surface requirements for the uniformity and symmetry of the irradiation, the synchronous control precision of multi-pulse was analyzed in detail. The results show that multi-pulse irradiation affects the synchronization of the energy distribution center in far-field directly. While one single beam pulse delay is greater than or equal to 2 times of the pulse width, the peak value of the light intensity on the target surface will fall down to 75%. If the control errors of two pulses are occurred with the same degree peak value of light intensity will fall down to 50%. Otherwise, when the control error of the pulse width is twice as large as the ideal pulse width, the peak value of the intensity on the target surface will drop to 87.5%.