Three-Dimensional Terahertz Computed Tomography Imaging Based on Thermomechanical Microcantilever Focal Plane Array

This paper reports a three-dimensional (3D) imaging technology based on a microcantilever focal plane array (FPA) operating at 2.52 terahertz (THz). Using the principle of photo-thermomechanical effect, a thermomechanical bi-material microcantilever array integrated with THz metamaterial absorbers (MAs) was designed and fabricated. The thermomechanical sensitivity of the FPA was measured to be 2.15 μm/K. To realize 3D THz imaging, a technology combining THz multi-angle projection imaging and computed tomography (CT) imaging was developed. 3D structures of different samples made of polytetrafluoroethylene (PTFE) were reconstructed successfully with the THz images obtained from the designed FPA and a 3D reconstruction algorithm.