Whole-field, high-resolution Fourier ptychography with neural pupil engineering

Fourier ptychographic microscopy (FPM) is a computational imaging technique that achieves high-resolution complex amplitude reconstruction across a large field of view. However, conventional FPM is fundamentally limited to regions near the optical axis due to violations of the shift-invariance assumption in off-axis areas, resulting in challenging edge-of-field-of-view reconstructions. We propose neural pupil engineering FPM, termed NePE-FPM, a physical model that dynamically shifts the pupil function position during reconstruction instead of fixing the pupil function in the center of the pupil plane. NePE-FPM engineers the pupil function using an implicit neural representation with multi-resolution hash encoding, enabling continuous, smooth shifting of the pupil function without introducing additional physical parameters. By optimizing a feature-domain loss function, NePE-FPM adaptively filters Fourier-space information from low-resolution measurements, achieving accurate off-axis reconstruction without modeling off-axis propagation. Experimental results demonstrate isotropic resolution of 1149 lp/mm across an 11mm 2 FOV using a 4×/0.1NA objective. The NePE-FPM bridges the gap between theoretical FPM capabilities and practical whole-slide imaging demands.