3D-META proposes an entirely new principle for beam steering of relevance to 3D imaging with lidar microsensors. Our proposed mechanism avoids the fundamental limitations associated with current MEMS tip-tilt micromirrors by instead using MEMS to tune the electromagnetic properties of gap surface plasmon metasurfaces. Using such dynamic metasurfaces we target a factor 10 increase in scanning angle range relative to non-resonant MEMS, while maintaining high precision in scanning angle. This translates into precise 3D imaging which competes with high-end precision lidar performance at reduced cost, size and technical complexity. Furthermore, gap surface plasmon (GSP) metasurfaces are known for their high optical efficiencies, thereby being able to bridge the gap in optical efficiency between micro-mirrors and gratings. Our proposed GSP metasurface therefore targets twice the optical efficiency of a grating surface, which will translate into lower optical power consumption by a factor two.

3D-META combines front-line metasurface expertise from the Nano Optics Group at the University of Southern Denmark (SDU) with world class optical piezo-MEMS development at SINTEF Microsystems and Nanotechnology (MiNaLab). The objectives of 3D-META are to (i) Design gradient GSP metasurfaces and non-resonant piezo MEMS for lidar micro-sensors, and  manufacture and characterise a proof-of-principle demonstrator for beam steering relying on already developed piezo-MEMS gap modulation at SINTEF Microsystems and Nanotechnology (MiNaLab). These objectives simultaneously target the industrial need for small, affordable, high resolution and efficient microsensors for 3D imaging, and the current scientific interest in developing platforms for dynamic modulation of metasurfaces. We believe that dynamic metasurfaces for lidar applications will benefit European society and its citizens in terms of more effective transportation, logistics, production and monitoring systems, and will enable the research field of metasurfaces to reach yet another important milestone in electromagnetic field control.