Abstract
Coherent degradation limits single-hologram height reconstruction in reflective off-axis digital holography. We propose PRI-Net, a two-stage network separating complex-field restoration from height inversion. Stage-I stabilizes the object-related complex field, while Stage-II uses low-, mid-, and high-frequency branches with object-region gating to recover platform baselines, boundaries, and local details while suppressing background responses. On physics-based paired simulations, PRI-Net achieves ROI-MAE and ROI-RMSE of 18.16 nm and 23.26 nm, reductions of 12.7% and 29.9% over the best single-stage baseline. Experimental reconstructions show improved morphology, while profilometer comparisons yield ROI-MAE and ROI-RMSE of 23.45 nm and 29.25 nm.