Large Area Electrically Tunable Lenses Based on Metasurfaces and Dielectric Elastomer Actuators

TL;DR

This paper presents the first electrically tunable flat lens using metasurfaces and dielectric elastomer actuators, enabling large focal length adjustments and dynamic optical corrections in a compact, lightweight device.

Contribution

It introduces a novel combination of metasurface optics with dielectric elastomer actuators for electrically tunable flat lenses with wide application potential.

Findings

Focal length tuning over 100% achieved.

Enabled dynamic corrections like astigmatism and image shift.

Demonstrated wide material compatibility through a water-based transfer process.

Abstract

Tunable optical devices, in particular, varifocal lenses, have important applications in various fields, including imaging and adaptive vision. Recent advances in metasurfaces, which control the wavefront of light using subwavelength-spaced nanostructures, open up new opportunities to replace bulk optical devices, with thin, flat, lightweight devices. We have demonstrated for the first time an electrically tunable flat lens, based on large area metasurfaces combined with a dielectric elastomer actuator having inline transparent electrodes, that is capable of simultaneously performing focal length tuning (>100%) as well as dynamic corrections, including astigmatism and image shift. This offers control versatility to flat optics hitherto only possible in electron microscopes. The water-based transfer process, which we describe, also enables wide compatibility across materials. The combination of metasurface optics and dielectric elastomer actuators enables a new, versatile platform for creating all kinds of tunable optical devices, through the design of tunable phase, amplitude, and polarization profiles.