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在基于光克尔效应的径向匀滑方案中，泵浦光脉冲序列利用非线性介质的光克尔效应对激光束附加周期性的球面位相调制，从而使激光束远场焦斑内部散斑产生周期性的径向扫动，以改善远场焦斑均匀性。为了分析泵浦光时间特性的改变对匀滑效果的影响，建立了径向匀滑方案的理论模型，并利用该模型对泵浦光的时间特性参数进行了分析及优化。结果表明，在泵浦光子脉冲之间的延迟时间一定时，子脉冲的脉宽过大或过小均会降低激光束远场的辐照均匀性，而随着子脉冲脉宽的增大，激光束远场的辐照均匀性随积分时间的波动相对趋于稳定，因而在避免产生明显“拍频”现象的前提下，选取较大的泵浦光子脉冲脉宽更有利于实现稳定的匀滑效果。激光束与泵浦光的时间同步精度对初期的匀滑效果有较大的影响，当泵浦光提前五分之一个周期左右时，可以在更短的积分时间内达到较好的径向匀滑效果。此外，不同的泵浦光时间波形所获得的匀滑效果也有所不同，当泵浦光的时间波形为三角波时，焦斑内部散斑的径向扫动速度较为稳定，可以使径向匀滑的整体效果及稳定性得到有效改善。
In the radial smoothing scheme based on the Kerr effect, the pump pulse sequence uses the Kerr effect of the nonlinear medium to add a periodic spherical phase modulation to the laser beam so that the laser spot far-field focal spot internal speckle A periodic radial sweep results to improve the uniformity of the far-field focal spot. In order to analyze the influence of the change of the pump time on the smoothing effect, a theoretical model of the radial smoothing scheme is established and the time characteristic parameters of the pump light are analyzed and optimized. The results show that when the delay time between pump pulses is constant, the pulse width of the sub-pulse is too large or too small, which will reduce the uniformity of laser beam far field. With the increase of sub-pulse width, The uniformity of the radiation in the far field of the laser beam tends to be stable with the fluctuation of the integration time. Therefore, choosing a larger pulse width of the pump photon pulse is more conducive to achieving a stable uniform under the premise of avoiding obvious “beat frequency” Slide effect. The time synchronization accuracy of the laser beam and the pump light has a great influence on the initial smoothing effect. When the pump light is about a fifth of a cycle ahead, a better radial direction can be achieved in a shorter integration time Smooth effect. In addition, different pump light time waveform obtained by the smoothing effect is also different, when the pump light time waveform is triangular wave, the focal spot speckle radial sweep speed is more stable, you can make radial smooth The overall effect and stability have been effectively improved.