The scientists used the bowl as a mold, filling it with a clear resin
and exposing it to ultraviolet light to solidify the material.
When Lee popped the hardened resin out of the mold, he had a
transparent dome a couple of millimeters in diameter and covered with
8,700 tiny mounds.
Next, the researchers used a component called a condenser lens to
shine a spoke-like pattern of ultraviolet light onto the dome so that
each spoke of light would hit the dome at a different angle.
Each of the tiny mounds worked like a lens to focus the incoming light
into the rest of the light-sensitive material beneath. The light
drilled into the material, creating 8,700 vertical channels, all pointing toward the center of the dome.
"One of the strengths of this work is that he has demonstrated that he
can do this thing very simply," said Edoardo Charbon, a professor and
expert in high-performance imaging at the Swiss Federal Institute of
Technology in Lausanne.
A cross-section of Lee's artificial compound eye looks remarkably
similar to a cross-section of a natural compound eye.
The idea, said Lee, is to place light-collecting components, such as
photodiodes or charge-coupled devices used in digital cameras, at the
bottom of the channels to capture the light signal and send it to a
processor.
Software would then convert the data coming from multiple
lens into a image appropriate for the final device, whether that's a
camera or a medical imaging device.
The challenges for Lee, said Charbon, lie in both science and
industry.
"If one can find a way to make this model easily standardized and be
handled by existing technological processes, then it has a great
future," said Charbon.
