The concept of cloaks capable of hiding objects and humans has been a favorite feature of many fictional films. Ironically, it might just turn into a reality with the help of LIGHT.
Invisibility or the state of being unseen is something dismissed by experts as fictional. The concept has always been used in many fantasy films such as Harry Potter. Who would forget how Mr. Potter used his famous ‘invisibility cloak‘ to walk around Hogwarts undetected?
The movie Predator also employed the concept of invisibility through its alien antagonist that uses a sophisticated cloaking device to hide in plain sight. However, even the movie itself showed that real-life application of invisibility could have flaws when the alien’s attempt to stay hidden was sabotaged by the distortion of light bending around it.
In essence, an object could be invisible if it doesn’t reflect nor absorb light. The question is: Could an object be truly invisible in reality?
It might seem like an impossible notion since objects can be seen by light in the visible spectrum from a source that reflects its surface and hits the viewer’s eye. But, if we will look for the most natural form of ‘invisibility’ in today’s world, the closest that we could find are the transparent clear glasses that allow light to pass through it.
Still, that’s not really invisibility. That’s transparency.
The search for the real-world invisibility formula may seem futile. But hold tight, a group of researchers might have found the solution to the mystery of the invisibility cloak!Researchers are one step closer to turning #invisibility cloak to reality!Click To Tweet
Invisibility Cloak: No Longer a Theory?
In theory, an invisibility cloak would work by smoothly guiding light waves around objects. In this way, the waves would ripple along their original trajectories like nothing’s there to block them.
However, a new study released by a group of researchers from the Technical University of Vienna used a different approach to make an object invisible. They made use of light they called a “beam of invisibility”.
In a statement, the study’s senior author, Stefan Rotter explained:
“Complex materials such as a sugar cube are opaque, because light waves inside them are scattered multiple times.
“A light wave can enter and exit the object, but will never pass through the medium on a straight line. Instead, it is scattered into all possible directions.”
During the study, the researchers used a completely opaque material that was then irradiated from above with a specific wave pattern. The effect allowed light waves from the left to pass through the material without any obstruction.
“To achieve this, a beam with exactly the right pattern has to be projected onto the material from above — like from a standard video projector, except with much higher resolution,” lead study author, Konstantinos Makris explained.
Rotter and his team viewed the result as an improvement that could open new possibilities for active camouflage to be achieved. Using their technique, Rotter said that he and his team do not want to re-route the light waves as what the existing theory implies.
Andre Brandstötter, a theoretical physicist from TUV and co-author of the study, was quoted as saying:
“Our goal was to guide the original light wave through the object, as if the object was not there at all. This sounds strange, but with certain materials and using our special wave technology, it is indeed possible.”
Right now, Rotter and his colleagues are conducting further experiments to see if their idea would actually work in real life setting.
“For me, personally, the most surprising aspect is that this concept works at all,” Rotter went on to say. “There may be many more surprises when digging deeper along these lines.”