激光与光电子学进展, 2019, 56 (2): 020501, 网络出版: 2019-08-01
基于二维光子晶体负折射的共聚焦系统 下载: 1107次
Confocal System Based on the Negative Refraction of Two-Dimensional Photonic Crystals
衍射 光子晶体 负折射 共聚焦 亚波长成像 超分辨成像 diffraction photonic crystals negative refraction confocal subwavelength imaging super-resolution imaging
摘要
基于二维光子晶体的负折射和亚波长成像特性,提出了一种可以实现超分辨成像的共聚焦系统,使用时域有限差分法(FDTD)仿真了共聚焦系统的聚焦和成像的过程。在焦点离光子晶体透镜下表面1.55 μm处,横坐标X =4 μm时,焦点半峰全宽(FWHM)为0.593λ ,小于入射波长,此时反射光在右侧像点的FWHM达到0.496λ ,实现了超分辨成像,并且随着焦点的右移,像点FWHM不断减小。同时,在针孔和焦点位置不变时共聚焦系统的轴向分辨率达到2.2λ 。
Abstract
In this study, a confocal system is proposed for which super-resolution imaging can be achieved based on the negative refraction and subwavelength imaging characteristics of two-dimensional photonic crystals (PCs). Further, the focusing and imaging processes of a confocal system are simulated with the finite-difference time-domain method. When the distance from the focus to the lower surface of a PC becomes 1.55 μm and when the transverse coordinate x=4, the full width at half maximum (FWHM) of the focus becomes 0.593λ, which is less than the incident wavelength; further, the FWHM of the reflected light in the right of the image point becomes 0.496λ, which indicates that super-resolution imaging can be realized. The FWHM of the image point decreases continuously when the focus shifts to right; further, the axial resolution of the confocal system becomes 2.2λ when the pinhole and focus are fixed.
牛金科, 梁斌明, 庄松林, 王国旭, 雷雨. 基于二维光子晶体负折射的共聚焦系统[J]. 激光与光电子学进展, 2019, 56(2): 020501. Jinke Niu, Binming Liang, Songlin Zhuang, Guoxu Wang, Yu Lei. Confocal System Based on the Negative Refraction of Two-Dimensional Photonic Crystals[J]. Laser & Optoelectronics Progress, 2019, 56(2): 020501.