New kind of invisibility cloak created
Did you ever wish that you could get up and about without being seen? You know, just to be like the invisible man, although it would be cooler if one had the choice of turning invisible and visible at will, and this includes the clothes that you come into direct contact with. Otherwise, you would have to walk to the wardrobe and wear something before turning visible again, unless you do not mind appearing to the rest of the world in your birthday suit. Alternatively, the fantasy world had always offered the idea of an ‘invisibility cloak’, where throwing this over you would render you invisible to anyone who looks your way. I can think of many naughty applications for such an item like this, but I guess the military would find a far more practical use for such an idea. Well, researchers over at the University of Texas in Austin have managed to come up with a spanking new, ultra-thin invisibility cloak that measures all of just 0.15mm – now is that thin or what?
Most of the invisibility cloaks that have been created until now come in large, cumbersome, desk-mounted machinations, and these will definitely stretch the definition of the word ‘cloak’, and they tend to lean more towards proof of concepts for the kind of invisibility material being tested, instead of being an actual invisibility cloaks. This particular invisibility cloak, however, measures a mere 166 micrometers thin, clearly making this a ‘cloak’ in every sense of the word.
Just how is this invisibility cloak achieved? Well, it uses something that is called a “metascreen,” which is made out of a 66µm-thick sheet of copper which has been attached to a 100µm-thick sheet of flexible polycarbonate. This particular cloak will then be attached to the object, which is an 18cm cylinder here, allowing the cloak to conform to the object’s shape perfectly. It is noted that the copper has been patterned in such a way for the scattered light from the cloak and the cloaked object to cancel each other out, hence resulting in its invisibility. How would you make use of a cloak like this?