Loading…

Deep Sub–Wavelength Focusing Metalens at Terahertz Frequency

With the benefits of non–invasive and low radiation, terahertz radiation has shown great potential in biomedical imaging applications. However, the low spatial resolution of the imaging system significantly affects its application in these fields. Although immersion techniques and super–oscillation...

Full description

Saved in:
Bibliographic Details
Published in:Photonics 2023-02, Vol.10 (2), p.222
Main Authors: Yang, Mengyu, Shen, Xin, Wen, Zhongquan
Format: Article
Language:English
Subjects:
Citations: Items that this one cites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:With the benefits of non–invasive and low radiation, terahertz radiation has shown great potential in biomedical imaging applications. However, the low spatial resolution of the imaging system significantly affects its application in these fields. Although immersion techniques and super–oscillation theory have achieved considerable success in improving the resolution of imaging systems, there are still problems with large focal spot sizes or large sidebands. Herein, a solid immersion lens based on super–oscillation is proposed to reduce the focal spot size when illuminated with circularly polarized light at a wavelength of 118.8 μm. The simulation results show that the lens can compress the full widths at half–maxima down to deep sub–wavelength scales, as small as 0.232 λ. At the same time, the maximum side–lobe ratio was 16.8%, which ensured that the device had a large field of view. The proposed method reveals new ideas in the field of super–resolution imaging.
ISSN:2304-6732
2304-6732
DOI:10.3390/photonics10020222