Pushing camera design beyond nature’s limits
URBANA, Ill. – A camera design inspired by the ocular systems found in insects, arachnids and crustaceans is being pushed beyond anything that exists in nature.
In the May 2 issue of Nature (doi: 10.1038/nature12083), an interdisciplinary team led by John A. Rogers of the University of Illinois at Urbana-Champaign describes a hemispherical-shaped camera comprising 180 lenses – each 0.4 mm in diameter – and miniaturized detectors that provide a nearly 180° field of view. The arthropod-inspired device measures 1 cm in diameter and is capable of IR imaging.
The resolution of this digital camera is comparable to that of the eye of a common fire ant. The system incorporates an array of rubber microlenses and silicon photodetectors in a thin, stretchable sheet that can be inflated like a balloon to form the final hemispherical shape.
Cameras with wide-angle fields of view and low aberration are difficult to build because they rely on bulk glass lenses and detectors constructed on the planar surfaces of silicon wafers, which cannot be bent or fixed, much less formed into a hemispherical shape. This type of curved design provides unmatched field of view and other powerful imaging capabilities.
“Nature has developed and refined these concepts over the course of billions of years of evolution,” said Rogers, the Swanlund Chair professor at the university.
Full 180° fields of view with zero aberration can be accomplished only with image sensors that adopt hemispherical layouts, as would be found in an insect eye.
“We are scaling the sizes of the cameras down and the number of lenses up,” he told Photonics Spectra. “We feel that we can move from the level of a fire ant, where we are now, to that of a dragonfly and, eventually, far beyond anything that exists in nature.”
The motivation behind the study was “based purely on curiosity and interest in establishing new design options in camera technologies,” he said. “It is somewhat less so on a specific, particular application.”
A digital camera inspired by the eyes of an arthropod and developed at the University of Illinois at Urbana-Champaign exploits large arrays of tiny focusing lenses and miniaturized detectors in hemispherical layouts.
However, two applications appear most promising: wide-angle surveillance and miniaturized endoscopes.
The researchers hope to move beyond the bug realm and into the water.
“We feel that we have sets of materials and schemes in fabrication that allow us to replicate and extend design principles found in many areas of biology, not just arthropods,” Rogers said. “Shrimp and lobster are interesting and different. Likewise for moths, lacewings and cephalopods.”
MORE FROM PHOTONICS MEDIA