illuminating science

I read a headline at Nature News today that got me pretty excited - engineers had devised an invisibility shield - a real one, something that would actually stop objects from reflecting or scattering light. But, when I read on, it turns out it only works for objects of around the same wavelength as light (i.e., less than a micrometer or one millionth of a metre) and it can only really work for monochromatic light, that is, light which contains only one colour like what comes out of a laser. Quite disappointing - but that’s part of selling your research, I guess - you’ve got to make it sound as interesting as you possibly can!

So, it looks like me plan for a Harry Potter-style invisibility cloak will have to be put on hold for the moment. On the other hand, that’s not to say that it’s impossible - there are a few people working on designing exactly that, mainly for military applications. There’s a cool article from a year ago which talked about making invisibility cloaks (another picture here) by making a cloak out of a giant flexible LCD screen. The demo image works simply by a camera recording what’s behind you, then a projector projecting it onto the front of you - it’s just a camera trick. But ultimately, you would build both display LEDs and cameras into the fabric so that the cloak displays what’s behind you on your front - just like the chameleon! Again, though, this might be a while coming. Guess for now I’m just going to have to settle for working on my Jedi mind tricks…