Move aside, flim-flam wizard of Oz. Move aside, magic red shoes. (I saw that Judy Garland's Oz dress sold for $480K this weekend.) We now have a magic invisibility cloak on the horizon. A team at Duke University in purple NC has perfected an invisibility device they premiered in 2006.
Scientists at Duke University have created the first invisibility cloak that perfectly hides centimeter-scale objects. While invisibility cloaks have been created before, they have all reflected some of the incident light, ruining the illusion. In this case, the incident light is perfectly channeled around the object, creating perfect invisibility.Does a one-centimeter screen mean we'll have magic cloaks? Apparently, yes. Or at least maybe. In a few years or so.
It is now just a matter of time before visible-light, omnidirectional invisibility cloaks are created.Somebody here will understand the stuff I don't, about metamaterials and such.
In theory, invisibility cloaks operate by bending electromagnetic waves around objects — so that instead of seeing the object, you see what’s behind the object. Negative index metamaterials get you most of the way, but they still need to be arranged in such a way that the illusion is perfect. To get around a 3D object, you have to turn a corner at some point — and previous cloaks have struggled to fashion metamaterials that bend waves around corners without causing reflections, which ruin the illusion. In this case, Nathan Landy, a graduate student at Duke University, tweaked the metamaterial itself, and then fashioned it into a diamond, which is apparently the best shape for minimizing reflections.
"Each quadrant of the cloak tended to have voids, or blind spots, at their intersections and corners with each other. After many calculations, we thought we could correct this situation by shifting each strip so that it met its mirror image at each interface," says Landy.I wonder what this will cost when it first hits the market. $450K?
"We built the cloak, and it worked. It split light into two waves which traveled around an object in the center and re-emerged as the single wave with minimal loss due to reflections."