Direct 3D Imaging through Spatial Coherence of Light

Wide-field imaging is widely adopted due to its fast acquisition, cost-effectiveness, and ease of use. Its extension to direct volumetric applications, however, is burdened by the trade-off between resolution and depth of field (DOF), dictated by the numerical aperture of the system. It is demonstrated that such trade-off is not intrinsic to wide-field imaging, but stems from the spatial incoherence of light: images obtained through spatially coherent illumination are shown to have resolution and DOF independent of the numerical aperture. This fundamental discovery enables to demonstrate an optimal combination of coherent resolution-DOF enhancement and incoherent tomographic sectioning for scanning-free, wide-field 3D microscopy on a multicolor histological section. Leveraging the spatial coherence of light enhances image resolution in traditional microscopy. A novel formalism demonstrates that the resolution of coherence-based systems is independent of numerical aperture, as confirmed experimentally. This property drives the development of scanning-free multicolor 3D microscopes, validated through histological sample analysis, with full potential for low-cost 3D imaging in real time. image