One of the more expensive parts of the cameras built-in to smartphones is the lens system. That’s because lenses have to be made in an entirely different way to the electronic components that make up the rest of the phone.
In recent years, physicists have hoped to change this with a new type of “metalens” that can be carved onto a flat sheet of silicon dioxide or similar material. Metalenses consists of pillars of silicon that are each about the same size as the wavelength of light.
These pillars interact with light, causing it to bend and scatter in precisely controllable ways. So by arranging large numbers of pillars in periodic arrays, physicists can make them bend light in the same way as a conventional lens.
