Inspired by nature, researchers have looked at the fish's retinal structure to design a contact lens that can adjust its focus and help treat a common eye disorder.
Making the most of the low light in the muddy rivers where it swims, the elephant nose fish survives by being able to spot predators amongst the muck with a uniquely shaped retina, the part of the eye that captures light.
"Imagine a contact lens that autofocuses within milliseconds. This could be life-changing for people with presbyopia, a stiffening of the eye's lens that makes it difficult to focus on close objects," said project's leader Hongrui Jiang from the University of Wisconsin-Madison.
Presbyopia affects more than one billion people worldwide, half of whom do not have adequate correction.
The new project requires overcoming several engineering challenges.
They include designing the lens, algorithm-driven sensors and miniature electronic circuits that adjust the shape of the lens, plus creating a power source - all embedded within a soft, flexible material that fits over the eye.
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In the new study, published in the journal Proceedings of the National Academy of Sciences, Jiang and his team focused on a design for the image sensors.
"The sensors must be extremely small and capable of acquiring images under low-light conditions, so they need to be exquisitely sensitive to light," Jiang noted.
The contact lens is able to focus on objects as small as 20 micrometers, roughly the width of the thinnest human hair.
They developed another type of lens inspired by the compound eyes of insects and other arthropods.
A prototype for clinical testing may still be five to 10 years off, Jiang said.
Once it's available, however, it may not cost much more than conventional contact lenses.