Equivalent source of reflector in finite‐different time‐domain for rapid analysis of corner scattering in terahertz computed tomography imaging

Abstract

We propose the equivalent source of reflector in finite‐different time‐domain (ESR‐FDTD) for rapid analysis of corner scattering in terahertz computed tomography (THz‐CT) imaging. The ESR‐FDTD is used instead of the reflector in the THz‐CT imaging system, which can significantly reduce the computational domain of the THz‐CT imaging system and effectively reduce the computational time and memory usage. The electric field distribution of the beam reflected by the reflector and that of the beam radiated from the ESR of the reflector are compared, and the results show that the electric field distributions of the reflector and its ESR are almost the same. The results of the corner scattering show that the phenomenon of corner scattering does not fully satisfy the behaviors of reflection and refraction. Therefore, the corner scattering cannot be accurately analyzed by the ray‐tracing method.