Iterative image method for apertureless THz near-field microscope

We propose a self-consistent calculation method for apertureless THz near-field microscope (NFM) which is based on an exact image theory. Within the quasi-electrostatic limit, the exact image theory was iteratively applied to calculate interactions between dielectric spheres and substrate effects. The calculated near field was in excellent agreement with results from a commercial finite element method (FEM) simulator.