re: I don't get it
Light waves are around the nanometer level in size. Hundreds of nanometers in fact. If we can build optics that, while not perfect exceed the diffraction limit, then we have a way to build scopes capable of resolving very tiny images, like planetary disks around other stars. Actually, I think interferometers will be the technology utilized to accomplish this imaging.
The small nanometer optical technology is a now demonstrable means of achieving that "negative index of refraction" goal by capturing these evanscent waves I'd never known about until recently.