Bio-inspired electrically tunable multi-focal metalens for intelligent imaging and near-eye displays

Inspired by the multi-layer polarization-sensitive structure of the Mantis Shrimp’s retina, we propose a multifunctional liquid-crystal multi-focal metalens (LC-MFM) for intelligent imaging and adaptive display. The device integrates a liquid crystal polarizer with a multi-focal metalens, enabling electrical switching of focal lengths through voltage control. A deep learning framework is employed to accelerate the inverse design of metaatoms that satisfy dual-polarization phase requirements. The fabricated LC-MFM achieves high focusing efficiency up to 68.8%, fast response times on the millisecond scale, and high resolution of >101 lp/mm. Two dynamic optical applications are demonstrated: an intelligent imaging system capable of real-time edge detection, image fusion, and depth-of-field prediction, and a compact augmented reality display that alleviates the vergence-accommodation conflict by dynamically adjusting virtual image depth. This work presents a novel paradigm that combines bio-inspired design, active metasurfaces, and machine learning for next-generation compact optical systems.