Yahoo – AFP, Mariette Le Roux, AFP News, 7 November 2012
 |
| A research scholar experiments with laser rays in a lab. Scientists said Wednesday they have developed a method to "see through" layers of thin, solid material in a breakthrough that holds promise for medical imaging, nanotechnology -- and the spy trade |
Scientists
said Wednesday they have developed a method to "see through" layers
of thin, solid material in a breakthrough that holds promise for medical
imaging, nanotechnology -- and the spy trade.
Still in
its infancy, the technique using laser and computer decoding has allowed a team
from the Netherlands and Italy to "see" an object behind a
non-see-through barrier made of ground glass.
Using the
same technology, they would also be able to look behind a sheet of paper or a
thin layer of paint, said study co-author Allard Mosk of the Institute for
Nanotechnology at the University of Twente in the Netherlands.
With
improvements, "20 years in the future I think we might have a device the
size of an iPhone that you could hold on the scattering material (the
non-see-through layer) and you push a button or maybe speak a command ... and
you'd be seeing what's behind it," the physicist told AFP.
Some
objects, like paper, skin or frosted glass, let through limited light, but
diffuse it so much that the human eye cannot see beyond them -- like trying to
see through fog.
The new
method works by shining a laser on the barrier, in this case a translucent
screen of ground glass made by an optics company. The disk does not allow any
light to pass through in a straight line but scatters it all.
The diffused
light that makes it through the glass then hits an object behind the screen,
which returns some of that light onto the backside of the screen, the team
wrote in the journal Nature.
This light,
by now completely scrambled and so low that it can no longer be seen by the
naked eye, is then analysed by a computer decoding programme that reproduces an
image of the hidden object, Mosk said.
"We
don't see the object itself, we don't see its shape, but thanks to our scanning
method all we really need to know is the amount of light," he explained.
Decoding
the light pattern "is like a huge puzzle and fortunately it's a puzzle of
the type that computers are very good at."
Mosk said
the technology could be useful for non-invasive scanning in medicine and in the
field of nanotechnology -- seeing inside a computer chip without having to open
it.
"In
principle, you could read a letter though an envelope, which might be good if
you are a spy."
Existing
technologies allow scientists to see through materials that partly, not
entirely, scatter light. And unlike the new technique, today's methods work by
using the non-scattered portion of light.
But don't
expect X-ray specs anytime soon, as the new laser technique could never work on
black, entirely light-absorbing surfaces, said Mosk, quipping that "a wall
would be quite a challenge".
Nor would
it be useful to the pursuits of Peeping Toms.
"Our
method is pretty good at looking through things, but before all kinds of
peepers try and call us: it is not good for looking through something sneakily
-- you would notice if someone points a very bright laser at you," the
scientist said.
No comments:
Post a Comment