摘要: This research focuses on improving the spatial resolution of terahertz (THz) imaging. Using a sub-wavelength aperture in a metal ground plane is the most common way to improve the spatial resolution, but a sub-wavelength aperture ... 展开 This research focuses on improving the spatial resolution of terahertz (THz) imaging. Using a sub-wavelength aperture in a metal ground plane is the most common way to improve the spatial resolution, but a sub-wavelength aperture has low radiation transmission. To increase the radiation transmission of a sub-wavelength aperture, periodic circular grooves were put in the metal around the aperture. The sub-wavelength circular aperture and the periodic circular grooves around it are known as the bull's-eye structure. The bull's-eye structure shows high radiation transmission at its design frequency, and it also has sub-wavelength spatial resolution. This research designed the bull s-eye structure to perform at approximately 3 mm wavelength in W band (75-110 GHz). Simulations were conducted on the 3D model of the bull's-eye structure to study its performance in the desired frequency range. Then a bull's-eye structure was fabricated and tested by the knife-edge technique to measure its spatial resolution. The knife-edge test results show the obtained sub-wavelength spatial resolution of the fabricated bull's-eye structure. This research also includes the designs of a 500 GHz bull's-eye structure and 100 GHz reflective probe. 收起