In the last decade or so, a group of scientists has begun to transform the field of optics by engineering flat optical metasurfaces (e.g. metasurface lens) that use an array of millions of microscopically thin and transparent fused-silica pillars to control phase, amplitude, and/or polarization of light.
The technology was selected as among the Top 10 Emerging Technologies by the World Economic Forum (WEF) in 2019, which remarked that such lenses would soon begin to be seen in smartphone cameras, sensors, fiber-optic components, and medical-imaging devices such as endoscopes. Now, researchers have taken a step toward making these metasurface lenses even more useful, by making them reconfigurable. They did this by harnessing nanoscale forces to infiltrate liquid crystals between the fused-silica pillars.
They infiltrated three different sorts of liquid crystals of different refractive index and birefringence, then evaluated the metasurface lens performance; the experimental results agree qualitatively with finite-difference time-domain solver (FDTD) simulation results. By electrically controlling the liquid crystal, the researchers will enable this new class of metalenses to reconfigure and structure light.