Chip‐Integrated Metalens for Near‐Infrared Imaging With Modulated Angular Response for Stray‐Light Suppression

Abstract

Stray‐light suppression is a fundamental requirement in a wide range of optical applications, such as astronomical observations, optical communications, high‐precision sensing, and high‐quality imaging. For example, conventional optical imaging systems usually rely on optical baffles to physically block stray light. However, these result in bulkiness and complexity of the system, and generally lack flexible and compact solutions for stray‐light suppression. Here, we propose a new strategy based on a metalens with modulated angular responses for simultaneous stray‐light suppression and wavefront modulation. Based on this dual‐function design strategy, we demonstrate excellent performance in near‐infrared far‐field imaging, in which image quality is significantly enhanced. Moreover, a more uniform intensity distribution is achieved in flat‐field imaging. Both imaging schemes are implemented directly on a CMOS sensor, offering a promising route toward image quality enhancement in compact and integrated optical systems.