光学学报, 2017, 37 (5): 0526001, 网络出版: 2017-05-05
π相位光阑调制的高数值孔径聚焦特性研究 下载: 543次
Study on High-Numerical-Aperture-Focused Characteristics by π Phase Diaphragm Modulation
摘要
利用半径较大的环形光阑使得聚焦区域产生较强的轴向电场分量, 用半径较小的环形光阑结合π相位板在聚焦区域形成轴向电场分布, 但电场振动方向与半径较大的环形光阑产生的轴向电场相反, 从而使得半径较大的环形光阑在聚焦区域形成的聚焦斑被整形, 在一定条件下可大大缩小光场聚焦斑的尺寸。研究结果表明, 相比使用单一环形光阑的情况, 这种方法可使得光场聚焦斑尺寸缩小40 nm以上。
Abstract
The strong axial electric field component can be obtained in the focus area by an annular diaphragm with a larger radius. In contrast, by another annular diaphragm with a smaller radius which combines with a π phase plate, the axial electric field distribution can be obtained in the focus area with the vibration direction opposite to that of the axial electric field produced by the annular diaphragm with a larger radius. Consequently, the focused spot formed by the annular diaphragm with a larger radius in the focus area is reshaped. In certain conditions, the size of the focused spot can be greatly reduced. The study results show that, compared with that when using sing annular diaphragm, the size reduction of the focused spot with the proposed method can be more than 40 nm.
蔡勋明, 赵晶云, 童红, 罗娇莲, 杨吟野, 李林福. π相位光阑调制的高数值孔径聚焦特性研究[J]. 光学学报, 2017, 37(5): 0526001. Cai Xunming, Zhao Jingyun, Tong Hong, Luo Jiaolian, Yang Yingye, Li Lingfu. Study on High-Numerical-Aperture-Focused Characteristics by π Phase Diaphragm Modulation[J]. Acta Optica Sinica, 2017, 37(5): 0526001.