Varifocal Alvarez metalens array for adaptive light-field imaging

Abstract

Abstract Metalens arrays hold great promise for compact light-field imaging systems owing to their compactness and wavefront shaping capabilities. However, their fixed focal lengths fundamentally limit depth-of-field modulation and axial scanning, restricting their adaptability to diverse light-field imaging scenarios. Here, we demonstrate adaptive light-field imaging using a varifocal Alvarez metalens array. The array is composed of two closely bonded metasurfaces, each patterned with 24 × 20 cubic-phase sub-regions. Through relative lateral displacement, the Alvarez metalens array achieves continuous focal length tuning from 3.33 mm to 4.50 mm. Integrated into a plenoptic imaging system, the proposed metalens array enables dynamic focusing and an expanded depth range. We further introduce a MultiLensFusion algorithm that combines these multi-focus captures into high-resolution, all-in-focus renderings. This work offers a compact and versatile platform for next-generation light-field imaging systems with dynamically tunable optical response.