Resolution Limits in Lens-Integrated CMOS THz Cameras Employing Super-Resolution Imaging

In this paper, we discuss the design choices of CMOS THz cameras for achieving maximum angular resolution and high sensitivity over a large bandwidth. In an active THz imaging set-up, the spatial resolution becomes a function of the object magnification, determined by the focal length of the collimating optic and the camera's angular resolution. The THz camera investigated experimentally here, under-samples its field-of-view for incident frequencies above 0.578 THz due to its 80-pm pixel pitch coupled with narrow pixel beams. With the help of super-resolution imaging, the camera reaches a measured angular resolution of 1.92° at 0.652 THz. At 0.822 THz, where the camera exhibits optimum NEP, the presented super-resolution model predicts an estimated angular resolution of 1.7°.