论文标题
通过亚波孔共振的超分辨率成像方法
A super-resolution imaging approach via subwavelength hole resonances
论文作者
论文摘要
这项工作通过使用亚波孔共振提出了一种新的超分辨率成像方法。我们采用了一个次波长结构，其中将一系列微小的孔蚀刻在金属板中，而相邻的距离$ \ ell $小于波长的一半。通过在谐振频率下调谐入射波，亚波长度结构产生了强大的照明模式，能够探测位于结构上方的成像样品的低空间频率成分。样品的图像是通过从衍射波的远场测量中进行稳定的数值重建获得的。证明可以为重建的图像获得$ \ ell/2 $的分辨率，因此可以通过在一个波长中排列多个孔来实现超分辨率。 所提出的方法可以在基于波的成像中找到应用，例如电磁和超声成像。它具有两个对实现实现重要的优势。它避免了以高精度控制探针和样品表面之间的距离的困难。此外，仅在数值重建中使用远场数据的低频带，数值重建的图像对于噪声非常稳定。
This work presents a new super-resolution imaging approach by using subwavelength hole resonances. We employ a subwavelength structure in which an array of tiny holes are etched in a metallic slab with the neighboring distance $\ell$ that is smaller than half of the wavelength. By tuning the incident wave at resonant frequencies, the subwavelength structure generates strong illumination patterns that are able to probe both low and high spatial frequency components of the imaging sample sitting above the structure. The image of the sample is obtained by performing stable numerical reconstruction from the far-field measurement of the diffracted wave. It is demonstrated that a resolution of $\ell/2$ can be obtained for reconstructed images, thus one can achieve super-resolution by arranging multiple holes within one wavelength. The proposed approach may find applications in wave-based imaging such as electromagnetic and ultrasound imaging. It attains two advantages that are important for practical realization. It avoids the difficulty to control the distance the between the probe and the sample surface with high precision. In addition, the numerical reconstructed images are very stable against noise by only using the low frequency band of the far-field data in the numerical reconstruction.
