Latest achievements in metalenses for advanced imaging applications

Metalens technology is rapidly advancing the frontiers of optical imaging by enabling flat, lightweight, and multifunctional alternatives to conventional refractive elements. Recent progress in improving efficiency, chromatic dispersion control, and scalable fabrication has positioned metalenses as pivotal components of next-generation optical platforms. In the first part of this review, we survey key developments in metalens design that address long-standing challenges in optics, including chromatic aberration, high-numerical-aperture focusing, and correction of higher-order aberrations such as spherical aberration and astigmatism. We then explore their integration into advanced imaging modalities, specifically multispectral, hyperspectral, and polarimetric systems, highlighting their role in enhancing imaging quality and operational capability. Finally, we discuss emerging applications in passive depth sensing, edge-enhanced imaging, and hybrid computational architectures, where deep neural networks are leveraged to restore broadband metalens-acquired images. Collectively, these innovations mark a paradigm shift in imaging science, with far-reaching implications for consumer optics, biomedical instrumentation, and industrial metrology, where compactness, performance, and integrability are paramount.