Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, China.
Opt Lett. 2011 Sep 15;36(18):3536-8. doi: 10.1364/OL.36.003536.
In a solid immersion lens (SIL)-based system, we predict theoretically that, by using the illumination of an azimuthally polarized beam with helical phase (APH), the subwavelength focusing can be simultaneously realized both in SIL and the third medium in spite of the presence of an air gap between the SIL and the third medium, which is not easily achieved in the case of the illumination of linearly, circularly, and radially polarized beams. For the APH illumination, the field in the focal region of the multilayered medium has no longitudinal component, and the on-axis intensity of the focused spot is nonzero. The APH illumination extends the capacity of SIL in realizing a supersmall focused spot, which is useful in microscopy, near-field optics, recording optics, and lithographic optics.
在基于固体浸没透镜 (SIL) 的系统中，我们从理论上预测，通过使用具有螺旋相位 (APH) 的角向偏振光束进行照明，即使在 SIL 和第三介质之间存在气隙，也可以在 SIL 和第三介质中同时实现亚波长聚焦，而这在使用线偏振、圆偏振和径向偏振光束照明的情况下不容易实现。对于 APH 照明，多层介质的焦区中的场没有纵向分量，聚焦光斑的轴上强度不为零。APH 照明扩展了 SIL 实现超小聚焦光斑的能力，这在显微镜、近场光学、记录光学和光刻光学中很有用。
