第 36 卷 第 3 期
2016 年 3 月
Vol. 36, No. 3
March, 2016
光 学 学 报
ACTA OPTICA SINICA
0326002-
椭圆环光阑对径向偏振光聚焦研究的影响
蔡勋明
1
赵晶云
2
范梦慧
3
罗姣莲
1
1
贵州民族大学贵州省普通高等学校绿色节能材料特色重点实验室, 贵州 贵阳 550025
2
浙江理工大学理学院, 浙江 杭州 310018
3
贵州民族大学理学院, 贵州 贵阳 550025
摘要 柱坐标下的径向偏振矢量光束在被高数值孔径透镜聚焦时,在紧聚焦条件下相比线偏振和圆偏振光束通过透
镜后能获得较小的聚焦斑。在聚焦透镜前加上椭圆环光阑后能强化在聚焦区域内的光场轴向分量,能在单一方向上
进一步缩小聚焦斑的尺寸。研究了径向偏振矢量光束经过椭圆环形光阑后的聚焦特性,在聚焦区域径向偏振分量形
成两个聚焦瓣,而轴向分量形成椭圆形的聚焦斑,并做了相应的物理解释。当增加椭圆环形光阑内环半径时,径向偏
振分量的聚焦瓣和轴向分量的聚焦斑单一方向聚焦尺寸均可小于光波长的三分之一,当进一步提高椭圆环形光阑内
环半径时,由于通光量减少和衍射效应,不能得到更小的聚焦尺寸。研究结果对于提高激光扫描显微镜的单向分辨
率具有重要意义。
关键词 物理光学; 偏振; 矢量光束; 光阑
中图分类号 O436 文献标识码 A
doi: 10.3788/AOS201636.0326002
Effect of the Elliptic Annular Aperture on the Focusing of Radially
Polarized Beam
Cai Xunming
1
Zhao Jingyun
2
Fan Menghui
3
Luo Jiaolian
1
1
Special and Key Laboratory of Guizhou Provincial Higher Education for Green Energy-Saving Materials, College of
Information Engineering, Guizhou Minzu University, Guiyang, Guizhou 550025, China
2
School of Science, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, China
3
School of Science, GuizhouMinzu University, Guiyang, Guizhou 550025, China
Abstract When the radial polarization vector beam is focused by a high numerical aperture lens, compared with
the linear polarization light and the circular polarized light cases, a smaller focused spot can be obtained by the radial
polarization vector beam. An elliptic annular aperture can enhance the axial component of light in the focus area.
So the focus spot size can be further reduced in one direction. The focusing characteristics of the radial polarization
vector beam passing through an elliptic annular aperture are studied. Two focusing lobes are obtained by the radial
polarization component of light. An elliptical focusing spot is obtained by the axial component of light and the
corresponding physical explanation is given. When the inner radius increases, the focus size of the focusing spot
and focusing lobes can be less than one third of the wavelength in one direction. When the inner ring radius of the
elliptic annular aperture is further improved, a smaller focus size of light can’t be obtained as the decrease of light
and the diffraction effect. The results of the study are important for improving one direction resolution of laser
scanning microscope.
Key words physical optics; polarization; vector beam; aperture
OCIS codes 260.2110; 260.1960; 140.3295
收稿日期: 2015-10-22; 收到修改稿日期: 2015-11-2
基金项目: 贵州省科学技术基金(黔科合 J 字 LKM[2013]19,黔科合 J 字[2014]2090)
作者简介: 蔡勋明(1978—),男,博士,副教授,主要从事量子光学与物理光学方面的研究。E-mail: caixm1997@aliyun.com
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