When I was a kid I always wondered what it would be like being invisible entering rooms unseen. One of the first books I read as a child was ‘the invisible man’ by H. G. Wells and I also watched several movies that were adapted from his famous science fiction novel.
Invisibility has been the theme for many other novels and movies but Japanese researchers are now a step closer in making it a reality. They have developed a hi-tech cloak which, worn by a person, makes him or her look “transparent.” The transparent cloak was made by using so-called retro-reflective projection technology. A camera fitted on the back of the cloak records what happens behind the wearer and projects the image on the front, creating the illusion that the person is transparent.
A computer processes the background imagery and relays it to a projector that filters through a half mirror and projects the scene onto the wearer. From a certain angle, the cloaked person looks transparent to onlookers.
Scientists are developing practical uses for this technology and hopefully it can be applied in future cars, helicopters, and planes, helping drivers and pilots to see “through” the vehicle as they operate it. It could for example help eliminate “blind spots” in the car, so that the driver notices easier a motorcyclist approaching from behind, or it could help a driver back the car up without the risk of hitting unseen obstacles. This technology would certainly reduce those unforeseen fender benders.
Physicists have had a fascination with light throughout the centuries and we see things because light reflects off of objects and hits our eyes.Light has properties that can be manipulated, which is how objects can be rendered invisible. Magicians, for instance will use mirrors to reflect light away from an object making the observer see the object disappear or seem invisible.
The United States Military has done extensive research on bending light around objects to render them invisible to the human eye. In the past however there have been little practical military uses for this technology. Our Defense Department has also spent Billions of dollars on camouflage that solders say doesn't quite work in combat situations.
Scientists however are developing a cloak that can have practical applications in combat. This cloak was developed by combining copper tape with polycarbonate, a material commonly used in DVD's and CDs. The resulting cloak has a miniscule pattern -- like a finely checkered shirt -- that neutralizes light waves bouncing off of it. For it to work, the material's pattern has to be roughly the size of the wavelength of light to be canceled out. That gives it a tightly limited range of waves it will work on.
It has no effect on a vast array of electromagnetic waves, which come in a myriad of sizes. The light waves we can see make up only a thin sliver of them.
Although the scientists say the principle behind the cloak at our present time could only be used to hide objects from the human eye. This is however "paving the way" to the development of advanced "camouflaging and invisibility." Our military has also developed ways to neutralize Microwaves that are used in radar detectors.
I never thought that the Science Fiction stories of my youth could one day become reality, especially, in my lifetime. Making objects magically disappear or rendering them invisible was something magicians did with mirrors. Perhaps future magicians will no longer rely on those mirrors to perform their disappearing acts but rather a common camouflage cloak will accomplish their grand illusions.
Only time will tell …….
Always with love from Suzhou, China
Thomas F O’Neill