Glass lenses, used in everything from smartphone cameras to microscopes, are bulky, heavy, and expensive. Now, a team of U.S. researchers has created high-power lenses from thin, flat arrays of nanosized towers of titanium dioxide that are thinner than a sheet of paper. The novel lenses are made from so-called metamaterials, engineered to control the way in which light waves interact (above). In this case, they are able to focus light across the visible spectrum. The setup allows them to magnify images up to 170 times with high resolution, as good as conventional state-of-the-art optics, the researchers report today in Science. The new lenses also have the potential to be fabricated—at much lower cost—with standard computer chip–making techniques. As a result, devices such as phones, tablets, and microscopes may soon be built with smaller, and cheaper, metalenses.