Neural network enabled wide field-of-view imaging with hyperbolic metalenses

TL;DR

This paper demonstrates that a neural network can correct off-axis aberrations in hyperbolic metalenses, enabling wide field-of-view imaging with high quality, trained solely on simulated data, thus avoiding extensive experimental data collection.

Contribution

The authors introduce a Restormer neural network approach to correct aberrations in hyperbolic metalenses, extending their FOV without additional experimental training data.

Findings

Achieved 54° FOV imaging with hyperbolic metalenses.

Neural network trained on simulated data effectively corrects aberrations.

High-quality imaging under diverse lighting conditions.

Abstract

The ultrathin form factor of metalenses makes them highly appealing for novel sensing and imaging applications. Amongst the various phase profiles, the hyperbolic metalens stands out for being free from spherical aberrations and having one of the highest focusing efficiencies to date. For imaging, however, hyperbolic metalenses present significant off-axis aberrations, severely restricting the achievable field-of-view (FOV). Extending the FOV of hyperbolic metalenses is thus feasible only if these aberrations can be corrected. Here, we demonstrate that a Restormer neural network can be used to correct these severe off-axis aberrations, enabling wide FOV imaging with a hyperbolic metalens camera. Importantly, we demonstrate the feasibility of training the Restormer network purely on simulated datasets of spatially-varying blurred images generated by the eigen-point-spread function (eigenPSF) method, eliminating the need for time-intensive experimental data collection. This reference-free training ensures that Restormer learns solely to correct optical aberrations, resulting in reconstructions that are faithful to the original scene. Using this method, we show that a hyperbolic metalens camera can be used to obtain high-quality imaging over a wide FOV of 54{\deg} in experimentally captured scenes under diverse lighting conditions.