Abstract
This paper presents a comprehensive investigation of solid and hollow polymer-based near-field imaging probes, each coated with a metallic layer on the outer surface, designed to operate in the THz frequency range. These probes are tailored to exploit the near-field properties of THz radiation for achieving sub-wavelength resolution imaging. The proposed probes exhibit a versatile design that has been rigorously examined through advanced electromagnetic simulations. The solid probe focuses on exploiting the dielectric properties of the material to manipulate THz radiation. Conversely, the hollow probe leverages its cavity structure to create resonant modes within the THz frequency range. This resonance phenomenon enhances the probe's ability to guide THz radiation, resulting in superior imaging capabilities. The metallic coating further enhances performance by efficiently coupling with THz waves, leading to improved resolution and signal-to-noise ratios. Overall, this paper presents a thorough investigation of solid and hollow polymer-based THz near-field imaging probes and experimentally demonstrates their effectiveness for high-resolution sub-wavelength imaging applications. These 3D printable probes offer versatile, cost-effective, and disposable imaging solutions for non-destructive material evaluation and sub-cellular scale imaging in various domains.