Taking their cue from nature, engineers have built a camera using
stretchable electronics that scans the world like a fly's compound eye
-- with a wide field of view and no distortion, they said.
The
digital device, which has a multitude of tiny, pliable lenses like
those found in ant, beetle and lobster eyes, also allows for a
near-infinite depth of field and high motion sensitivity, the team wrote
in the journal Nature.
"We've figured out
ways to make cameras that incorporate all of the essential design
features of eyes found in the insect world," study co-author John Rogers
of the University of Illinois' engineering department told AFP.
"The
result is a new type of camera that offers exceptionally wide-angle
fields of view (nearly 180-degrees) with zero aberrations and uniform
illumination intensity."
Most classical
cameras mimic the working of the animal eye: light reflected off an
object passes through the lens which bends and focuses the light onto
the retina at the back of the organ, where nerve cells convert it into
electric impulses sent to the brain, which produces an image.
These
single-lens systems have a limited field of view, but insects and other
species with eyes composed of multiple units, called ommatidia, enjoy
panoramic vision.
"Nature has developed and refined these concepts over the course of billions of years of evolution," said Rogers.
Conventional
single, wide-angle camera lenses, like fish-eye lenses, distort images
on the periphery because of a mismatch between the light entering
through a bent lens surface only to be captured on a flat detector.
Most electronics used in detectors are made of a brittle silicon which cannot be bent.
For
their camera, the team created stretchable electronics to build a
detector that can be curved into the same hemispherical shape as the
lens -- eliminating distortion.
The camera,
about 1.5cm (0.6-inch) in diameter, has 180 miniature lenses, each with
its own detector -- similar to the number found in fire ant and bark
beetle eyes.
Dragonflies have about 28,000 lenses and worker ants about 100.
The electronics and lenses are both flat when manufactured -- allowing them to be made with existing methods.
"This
is the key to our technology," co-author Jianliang Xiao, electrical
engineering assistant professor at the University of Colorado in
Boulder, said in a statement.
"We can fabricate an electronic system that is compatible with current technology. Then we can scale it up."
The technology could be useful in surveillance cameras or endoscope imaging, said Rogers.
But
commercialisation is some way off, as a useful camera would likely need
millions of lens-detector combination units -- requiring much
investment into manufacturing capacity.
