Fractal Antenna Systems,
Inc., the pioneering innovator of fractal antenna and fractal electronics
technology, today announced that it has filed for patent protection on a system
for making a wideband invisibility cloak turn on and off. The invention sets
a path for the realization of a practical invisibility cloak that not only makes
an object disappear, but allows the cloaked object to see through the cloak,
with the flick of a switch.
“Previous cloak descriptions had a fatal flaw that no one knew how to
address: when you cloak you also make the object ‘blind’ as well,”
notes inventor Nathan Cohen. ”Of course, you can physically remove the
cloak, but that is totally impractical. What we’ve been working on for
some time are ways of changing the electromagnetic characteristics of the cloak,
on the fly, and that changes the cloak into a kind of lens, that you then can
see out of.” Since the switching can be done rapidly, the invisibility
cloak can blink on and off at will and is a ‘cloak-on-command™’.
The firm pioneered and demonstrated the world’s first practical invisibility
cloak, operating at microwaves. Previous and more recent invisibility cloaks
are either narrow in frequency range (and thus impractical) or merely mirrors
with a corrective set of layers that removed the mirror’s reflected distortions.
”I still haven’t figured out the advantage of calling a mirror a
‘cloak’—who wants to hide behind a mirror-- but that’s
what many other scientists find curiously exciting,” notes Cohen who added:
“no smoke and no mirrors here.”
The firm’s invisibility cloak technology is built around patented and
patent pending arrangements of close packed fractal resonators, a fractal metamaterial,
that uniquely enable the operation of the cloak. Fractals are fascinating geometric
shapes that repeat a pattern over several size scales. The switching feature
takes advantage of the fractal nature of the cloak.
Cohen cautioned that no invisibility cloak now works at visible light, except
ones on pinhead sized scales, “People have high expectations, despite
our continued cautions that Harry Potter and Klingons aren’t lurking in
the shadows.” Instead, the firm sees practical uses of invisibility cloaking
for defense, telecom, and energy needs, mostly at microwave and IR wavelengths,
with later applications at visible wavelengths in the future.
Fractal Antenna Systems, Inc. supplies products for the world’s most
demanding wireless, and electromagnetic applications. Backed by eighteen U.S.,
and international patents, plus numerous patents pending, Fractal Antenna Systems
is the recognized pioneer in fractal technology, with extensive research and
field experience over 15 years in business. The company is a privately held
and headquartered in Waltham, Massachusetts, USA.