Time-domain Terahertz Imaging with a Plasmonic Photoconductive Terahertz Source Array

We present a spatiotemporally encoded terahertz time-domain imaging system that eliminates the need for raster scanning by enabling single-shot acquisition of spectral, temporal, amplitude, and phase information across an entire image. A 30×30 plasmonic terahertz source array, with each element uniquely temporally modulated, illuminates corresponding points on the object, while a single-pixel plasmonic detector captures the combined response. Decoding these temporal signatures reconstructs the full time-domain terahertz signal at every pixel with high signal-to-noise ratio. The system achieves high-throughput, large-field-of-view, high-resolution imaging, demonstrated through imaging phase objects with a 0.66 mm lateral resolution, less than 10 µm depth resolution, and a 24×24 mm² field of view over a 1.5 s image acquisition time – orders of magnitude faster than conventional time-domain terahertz imaging systems.