Phase Tomography using Axial Structured Illumination

This work explores a new approach to holographic tomography (HT) that reconstructs three-dimensional refractive index (RI) distributions or phase using axial structured illumination instead of conventional multi-angle illumination. While iterative optimization methods have improved HT reconstruction quality, most systems still rely on complex multi-angle setups. Through simulations and experiments, this study demonstrates that cross-talk–free, slice-by-slice 3D RI reconstruction is achievable using on-axis structured illumination combined with sparsity constraints, provided the slice spacing follows an effective depth-of-focus design rule. The results establish the feasibility of a simplified Axial Structured Illumination Tomography (ASIT) system, requiring only minimal modification of standard digital holographic microscopes.