May 3, 2006— A three-dimensional optical system based on the eyes of honeybees,
houseflies, and dragonflies could allow cameras to see in 360.
The artificial compound eye, reported in the current issue of Science
by Luke Lee and his team at the University of California, Berkeley, could be on the market within a few years in ultra-thin camera phones or in small, surveillance camcorders.
"You can capture an image from 0° to 180°. If you have
two artificial compound eyes ... you can have a 360° field of view,"
said Lee.
An insect's domed eye is covered in thousands of tiny
lenses that capture light from different angles. Each lens caps a
vertical channel that funnels the light to photoreceptor cells, which
transmit the light signal to the creature's optic nerve.
Humans have just one lens.
In the past, researchers have tried to replicate the insect system using
expensive conventional techniques typically used to manufacture
semiconductor chips.
But those methods so far have only produced two-dimensional compound eyes that don't give the
highly desired wide field of view.
Ideas from Nature
Lee and his team borrowed from nature to produce a 3-D
domed eye that has thousands of light-guiding channels almost
identical to those found in insects.
For starters, they designed a template in a piece of photo-sensitive
polymer, laying out 8,700 tiny microlenses in a hexagonal honeycomb
pattern. On top of those they placed a thin layer of an elastic
polymer.
The researchers then attached the flexible layers over the opening of a
vacuum chamber and applied a negative air pressure. The pressure
pulled the membrane into a bowl shape and also caused the surface to
dimple at each of the 8,700 tiny mounds.
