Study on the Terahertz Vortex Imaging based on Spiral Phase Plates

A novel terahertz (THz) imaging method based on vortex wave is presented. First, the analytical expression of field distribution of the THz vortex beam generated by spiral phase plate (SPP) is derived, and the propagation characteristics of vortex beams with different topological charges are analyzed. Subsequently, the THz vortex imaging model is established, and Fourier transform (FT) is used to reconstruct the target’s azimuthal image. Simulation results demonstrate that vortex beam has the prospect for acquiring the azimuthal information of target. The work can also promote the development of the novel THz imaging technology.