Dual-Control Tunable Metalens With Large Zoom Range

Tunable metasurfaces present a novel approach to compact planar optics development. However, most tunable metasurfaces limit dynamic adjustability due to a single control method. In this study, we investigate the potential of integrating polarization with elastic materials and showcase a tunable metalens that leverages both polarization and stretching control. The tunable range through stretching is measured at 11.4 to 20.6 μm for x-polarization and 20.7 to 36.4 μm for y-polarization. The zoom range achieved is 213.8% of the minimum focal length. The metalens demonstrate a focusing efficiency of over 30% and almost diffraction-limited focusing. Additionally, we fabricate metalenses with polarization-only and stretch-only controls for comparison purposes. Our results indicate that the dual control approach effectively addresses the limitations of conventional polarization-multiplexed metalenses in achieving continuous zoom capability. Furthermore, compared to single-control tunable metalenses, the dual control metalens exhibits a significantly wider adjustable zoom range. We anticipate that this design holds promising application prospects in VR/AR display and holographic imaging.