Driving Sub-Wavelength Resolution in Terahertz Imaging with Mesoscale Lenses

A detailed investigation into the enhancement of terahertz (THz) detection via the terajet effect was conducted using mesoscale dielectric lenses of varying shapes and sizes. Polytetrafluoroethylene (PTFE) lenses—including spherical, aspherical, and cubic geometries—were fabricated and tested at 0.15 THz and 0.3 THz. The results revealed improved responsivity and lower noise equivalent power (NEP), with performance strongly influenced by frequency and lens shape. Notably, aspherical lenses exhibited superior spatial resolution at 0.3 THz while spheric lenses demonstrated higher signal enhancement at the same frequency. These findings highlight the potential of the terajet effect to advance THz detection for applications such as medical imaging, security screening, and non-destructive testing, while offering practical design insights for optimizing THz system performance.