This futuristic camera lens is super tiny, totally flat, and relatively cheap

Harvard researchers have developed a novel, flat lens they say can focus "all the colors of the rainbow." This is a significant departure from the camera lenses made today, which are curved, bulkier, and take up more space.
But there's a catch: The researchers successfully focused light with this lens, which they call a "metalens," but on an extremely small, nanoparticle scale (nanoparticles can be thousands of times thinner than a human hair). While an impressive feat, major tech companies like