Inspired by the compound eyes of a species of trilobite, researchers at NIST developed a metalens that can simultaneously image objects both near and far. This illustration shows the structure of the lens of an extinct trilobite. Credit: NIST
Phys.org has a story about technology derived from fossils. Some researchers at NIST have took inspiration in the eyes of the trilobite Dalmanitina socialis to make special bifocal lenses for a miniature camera. Their work can be found in a recent paper published in the journal Nature Communications.
Five hundred million years ago, the oceans teemed with trillions of trilobites—creatures that were distant cousins of horseshoe crabs. All trilobites had a wide range of vision, thanks to compound eyes—single eyes composed of tens to thousands of tiny independent units, each with their own cornea, lens and light-sensitive cells. But one group, Dalmanitina socialis, was exceptionally farsighted. Their bifocal eyes, each mounted on stalks and composed of two lenses that bent light at different angles, enabled these sea creatures to simultaneously view prey floating nearby as well as distant enemies approaching from more than a kilometer away.
Inspired by the eyes of D. socialis, researchers at the National Institute of Standards and Technology (NIST) have developed a miniature camera featuring a bifocal lens with a record-setting depth of field—the distance over which the camera can produce sharp images in a single photo. The camera can simultaneously image objects as close as 3 centimeters and as far away as 1.7 kilometers. They devised a computer algorithm to correct for aberrations, sharpen objects at intermediate distances between these near and far focal lengths and generate a final all-in-focus image covering this enormous depth of field.
Such lightweight, large-depth-of-field cameras, which integrate photonic technology at the nanometer scale with software-driven photography, promise to revolutionize future high-resolution imaging systems. In particular, the cameras would greatly boost the capacity to produce highly detailed images of cityscapes, groups of organisms that occupy a large field of view and other photographic applications in which both near and far objects must be brought into sharp focus.