Figure 2.

Phase retrieval process: (a) electron hologram; (b) digital diffractogram obtained through FFT of (a), with the yellow circle indicating a specific frequency zone selected for inverse FFT (FFT⁻¹); (c,d) real and imaginary components of the complex image reconstructed from the hologram via FFT⁻¹; (e,f) real and imaginary components after noise reduction applied to (c) and (d), respectively; and (g) reconstructed phase image derived from ${\tan }^{-1}i/r$. Reprinted from [89], Copyright (2024) by Springer Open.