Reflective Single-Pixel Terahertz Imaging Based on Compressed Sensing

The investigation of single-pixel terahertz (THz) imaging opens up a new research direction for the development of THz imaging technology. In this work, we exploit a reflective single-pixel THz imaging system based on photoinduced dynamic masks. By combining the compressed sensing and inverse Fresnel diffraction algorithms, a reflective THz spectral image is accurately reconstructed and the morphology of a sample is clearly observed. Three application potentials of the THz imaging system are fully proved, including time-of-flight measurement of a sample with multiple interfaces, noninvasive testing of a hidden object, and spectral identification of different chemical substances. The reflection-type measurement mode effectively improves the practicability of single-pixel THz imaging.