通过数值模拟,比较了高能激光及其采样后在湍流大气中传输时远场中央长曝光斑的环围能量半径与扩展等情况。结果表明,在仅有湍流时两者保持不变,而热晕会导致光斑的进一步扩展;采样器的透光比越低,热晕对光斑的扩展影响越小;未采样高能激光的远场中央光斑相对于高能激光经采样后的远场中央光斑的扩展,可归因于热晕效应。因此,利用光束波前采样器对高能激光及其采样后在湍流大气中传输时的远场光斑特性进行比较,就可以诊断高能激光大气传输热晕效应。

The ringed-energy-radius and expansion of the long-exposed far-field central patterns of the high-energy (HEL) laser and its sampled one propagating in the turbulent atmosphere are compared by numerical calculation, the results show that: both of them are the same in the merely turbulent situation, and the thermal blooming leads to attached expansion of the pattern; the smaller the transmission of the sampler is, the less the effect of thermal blooming on the attached expansion of the pattern is; the attached expansion of the central pattern of the high-energy laser with respect to its sampled one is due to the thermal blooming. The atmospheric thermal blooming effects thus can be diagnosed by the methods of utilizing the beam wavefront sampler and comparing the characteristics of the far-field central patterns of the high-energy laser with its sampled one propagating in the turbulent atmosphere.