Invisibility

摘要

If you want to make something invisible to an infrared or radio receiver, cloak the object in a plastic shell covered with a pattern of ultra-fine copper or silver lines. Called a metamaterial, this surface acts like thousands of tiny repeating antennas. When that infrared beam or radio wave hits one "antenna," the signal gets passed to the next and then the next and so on, eventually getting seamlessly relayed around the object. The receiver never registers that the signal encountered interference. To it, the object in question is invisible. Now move along the electromagnetic spectrum from infrared to visible light and everything should work the same way, right?