In a report posted in Science Magazine, material scientists have found a way to replace glass lenses, like the ones used in cameras and microscopes, with ones made of flat "meta-surfaces", which are lighter and smaller—like—way smaller. What are "meta-surfaces"? Well, they're "specially designed two-dimensional arrays of nanometer-scale metallic antennas [that] may allow bulky optical components to be shrunk down to a planar device structure." Duh. If that made no sense to you (you're not alone), here's a video that explains it more simply:
These "metalenses", which focus light by arranging "tiny towers" of titanium dioxide in specific patterns, will be just 2mm across and thinner than a strand of human hair. And other than drastically reducing size, metalenses will do away with aberrations produced by spherical glass lenses.
Here's what the senior author of the report, Harvard University's Federico Capasso, told the BBC about the metalens:
In my opinion, this technology will be game-changing. The lens is quite unlike the curved disks of glass familiar from cameras and binoculars. Instead, it is made of a thin layer of transparent quartz coated in millions of tiny pillars, each just tens of nanometres across and hundreds high.
Singly, each pillar interacts strongly with light. Their combined effect is to slice up a light beam and remould it as the rays pass through the array.
The quality of our images is actually better than with a state-of-the-art objective lens. I think it is no exaggeration to say that this is potentially revolutionary.
You should definitely read the rest of the BBC article to learn more about Capasso's findings, as well as the full report published in Science Magazine.
Source: Science Magazine