Sharper focal spot formed by higher-order radially polarized laser beams
Sharper focal spot formed by higher-order radially polarized laser beams
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DOI：
10.1364/josaa.24.001793
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发表时间：
2007-06-01
影响因子：
1.9
通讯作者：
Sato, Shunichi
中科院分区：
文献类型：
--
作者：
Kozawa, Yuichi;Sato, Shunichi
基于矢量衍射理论，计算了含有高阶横模的径向偏振激光束在焦点附近的光强分布。对于高阶径向偏振模光束以及基模（R-TEM 01 *）光束，强纵向分量在高NA聚焦条件下在焦点处形成更尖锐的光斑。特别地，双环径向偏振模（R-TEM 11 *）光束由于内外环之间具有π相移的相消干涉，可以有效地减小焦斑尺寸。与NA = 1的R-TEM 01 * 光束聚焦相比，R-TEM 11 * 光束的焦斑半高宽纵向分量减小了13.6%，总强度减小了25.8%。(C)2007年美国光学学会
The intensity distributions near the focal point for radially polarized laser beams including higher-order transverse modes are calculated based on vector diffraction theory. For higher-order radially polarized mode beams as well as a fundamental mode (R-TEM01*) beam, the strong longitudinal component forms a sharper spot at the focal point under a high-NA focusing condition. In particular, double-ring-shaped radially polarized mode (R-TEM11*) beams can effectively reduce the focal spot size because of destructive interference between the inner and the outer rings with pi phase shift. Compared with an R-TEM01* beam focusing in a limit of NA = 1, the full width at half-maximum values of the focal spot for an R-TEM11* beam are decreased by 13.6% for the longitudinal component and 25.8% for the total intensity. (C) 2007 Optical Society of America