对高功率激光进行了研究.以平顶高斯光束为例,推导出了它通过无光阑和有光阑的近轴ABCD光学系统传输的解析表达式.给出了它的特征参数,包括光束传输因子(M²因子)、陡峭度(K参数)和桶中功率(PIB)并作了物理分析.最后,指出高功率激光光束控制应使光束在靶面上的功率/能量集中度、时间和空间波形、瞄准稳定性以及时间持续性等指标满足应用要求.

The subject how to characterize high-power lasers is studied. The flattened Gaussian beam (FGB) is taken as an illustrative example, and the propagation of FGBs passing through unapertured and apertured paraxial ABCD optical systems is expressed in the analytical form. The beam characteristic parameters including the beam propagation factor (M² factor), kurtosis (K parameter) and power in the bucket (PIB) of FGBs are given and analyzed physically. Finally, it is pointed out that from a practical point of view the beam control of high-power lasers means that the power/energy focusability on the target, temporal and spatial profile, pointing stability and sustainability of beams should satisfy application requirements. It is a challenging subject in modern optics and laser technology.