The evolution of incoherent digital holography: A perspective on concepts, technologies, and impact (invited)

Incoherent digital holography (IDH) has transformed from a conceptual curiosity to a versatile imaging framework capable of wide applicability. This perspective article traces the evolution of the IDH field through key advances in self-interference architectures, notably FINCH and its derivatives, and recent developments in multiplexed, computational, and coded aperture model-based imaging and reconstruction strategies. Drawing on contributions by leading researchers in the field, we highlight how optical design, diffractive elements, polarization sensors, and computational algorithms have jointly expanded all the facets of IDH systems. We discuss the physical principles enabling incoherent holography, its unique capacity for super-resolution imaging, quantitative phase imaging, daily light imaging, and its increasingly prominent role in microscopy, 3D sensing, and biomedical imaging. Finally, we outline open challenges, including system integration, reconstruction noise, and artefacts. In this context, we identify emerging trends that may shape the future of incoherent digital holography. This article aims to provide a unified perspective on the conceptual foundations, technological maturation, and scientific impact of this rapidly advancing field.