Scientists create invisibility cloak
A pair of researchers have discovered a way to arrange four lenses to act as a working cloaking device that can be seen from several angles. Joseph Choi and John Howell led the project at the University of Rochester, and the paper was reported to the journal Optics Express. “There’ve been many high tech approaches to cloaking and the basic idea behind these is to take light and have it pass around something as if it isn’t there, often using high-tech or exotic materials,” Howell said in a press release.
Though there have been functional invisibility cloaks that block objects from being detected with radar, electromagnetic radiation, touch, and sound, but this lens prevents objects from being detected optically. Scientists had to allow the background to be seen and carefully coordinate the power of the lens with the distance from one another.
“This is the first device that we know of that can do three-dimensional, continuously multidirectional cloaking, which works for transmitting rays in the visible spectrum,” Choi added.The secret is not focusing the light straight through the center of the lenses. “This cloak bends light and sends it through the center of the device, so the on-axis region cannot be blocked or cloaked,” explained Choi.
