截断Gauss光束远场参数预估  

Estimation of Far-Field Parameters of Truncated Gauss Beams

作　　者：关奇[1] 杜太焦[1] 陈志华[1] 闫伟[1] 高银军[1] 张冬晓 GUAN Qi;DU Taijiao;CHEN Zhihua;YAN Wei;GAO Yinjun;ZHANG Dongxiao(Northwest Institute of Nuclear Technology,Xi’an 710024,China)

机构地区：[1]西北核技术研究所,西安710024

出　　处：《现代应用物理》2022年第3期39-46,共8页Modern Applied Physics

基　　金：国家自然科学基金资助项目(12105227)。

摘　　要：针对激光在大气中传输时受到大气吸收、大气散射、衍射和大气湍流等因素引起的光束质量下降等问题,采用理论分析和数值模拟相结合的方法,给出了不同截断情况的Gauss光束经过大气传输后远场光斑63.2%环围能量半径的计算公式。计算了不同传输距离和不同高度情况下,目标处直径为5 cm圆域内的平均功率密度,并根据上述结果分析了不同截断情况下的最大毁伤距离。结果表明:平均功率密度随传输距离的增加呈指数衰减;由于湍流影响,发射仰角越大,最大毁伤距离越远;发射口径不变时,最大毁伤距离随发射光束束腰的大小而变化,束腰半径在0.5倍发射口径附近,毁伤范围最大;毁伤阈值为2 W·cm^(-2)时,最大毁伤高度约为最大毁伤水平距离的2倍。In this paper,theoretical analysis and numerical simulation are combined to give a formula for calculating 63.2%beam energy radius of the far-field spot of Gauss beams with different truncation conditions after laser propagation in the atmosphere.In addition,the average power intensity in a 5 cm diameter circle on the target is calculated under different horizontal distances and different heights according to the assumption that the profile of laser intensity on the target is Gaussian distribution.The maximum damage range of laser beams under different truncation conditions are analyzed according to the above results.The results show that the average power intensity decreases exponentially with the increase of the propagation range,and the maximum damage range changes with the elevation angle of the laser beams due to the effect of atmospheric turbulence.Besides,when the launch aperture is unchanged,the maximum damage range varies with the size of the beam waist.The beam waist radius is near 0.5 times the aperture diameter,the damage range is the largest.When the damage threshold is 2 W·cm^(-2),the maximum damage height is about 2 times the maximum damage horizontal distances.

关 键 词：激光传输 大气湍流 光纤激光 

分 类 号：TN241[电子电信—物理电子学] O434[机械工程—光学工程]