But this cloak, and others like it, were a far cry from anything you’d read about in a Harry Potter book or see in a Star Trek episode (*required references in any article about invisibility cloaks*). One of the major problems, according to a new paper from Dr. Andrea Alú from the University of Texas (Austin), is that while it makes objects invisible in one frequency, it actually makes them more visible under another frequency. An object made invisible in red light, for example, would be even more visible in blue light.

But Alú says he has invented a new type of device that fixes that problem. Like the cloaks of yore, Alú’s new design uses meta-materials (synthetic textiles with properties not found in nature) that can bend light around an object and make it look like it’s not there. But, by adding an electronic source like a batter to the cloak (making the cloak “active” as opposed to “passive”), Alú says he can make objects transparent at “all angles and over all broad bandwidths.”