摘要
基于功率密度的二阶矩方法,推导出了非傍轴旋转对称拉盖尔-高斯(LG)光束远场发散角的解析公式,并表示为伽玛函数的幂级数求和形式。计算结果表明,当初始束腰宽度和波长之比w0/λ趋于0时,对任意非傍轴旋转对称LG光束,远场发散角趋于渐近值63.435°,与阶数无关。对于p=0的特例,则退化为非傍轴高斯光束的结果。
Based on the second-order moment of the power density,the far-field divergence angle of nonparaxial rotationally symmetric Laguerre-Gaussian（LG） beams is derived and expressed in a sum of the series of the Gamma function. It is shown that the far-field divergence angle of nonparaxial rotationally LG beams approaches to an asymptotic value of 63. 435° as the initial walst-wldth to wavelength ratio ω0/λ approaches zero, which is independent of the order. For the special case of p = 0 our result reduces to that of nonparaxial Gaussian beams.
出处
《激光技术》
CAS
CSCD
北大核心
2006年第2期181-182,185,共3页
Laser Technology
基金
国家高技术基金资助项目(A823070)
关键词
激光光学
非傍轴拉盖尔-高斯光束
功率密度
发散角
laser optics
nonparaxial Laguerre-Ganssian（LG） beam
power density
divergence angle
