Photonics Breakthroughs 2025: Programmable Lensless Imaging With a Fresnel Zone Aperture

Optical imaging has long been dominated by conventional lens-based systems, which, despite their success, remain constrained by size, weight, and cost. Lensless imaging seeks to overcome these limitations by replacing lenses with thinner, lighter, and cheaper optical modulators and reconstructing images computationally, while facing trade-offs in image quality, artifacts, and flexibility inherent in traditional static modulation. Here, we review recent progress in lensless imaging and highlight a recent advance based on a programmable Fresnel zone aperture (FZA), termed LIP, which addresses these challenges through optimized aperture design and reconstruction strategies. By establishing an optimal parameter matching criterion and introducing an offset-FZA parallel merging strategy, LIP achieves high-quality reconstruction with reduced artifacts. Experimentally, LIP achieves a 2.5-fold resolution improvement and a 3 dB signal-to-noise-ratio gain in the static mode, while maintaining an interactive frame rate of 15 fps in the dynamic mode. We further discuss lens-based HoloFZA as an extension of programmable FZA modulation and discuss the broader significance, current limitations, and future prospects of lensless imaging toward compact, high-quality, and multifunctional visual sensing.