Home > Chemical > Realistic Retinas Make Better Bionic Eyes

Realistic Retinas Make Better Bionic Eyes

New visual sensors inspired by the human eye could help the blind see again and provide powerful new ways for machines to sense the world around them. Recent research shows that more faithfully copying nature’s hardware could be the key to replicating its powerful capabilities.

Efforts to build bionic eyes have been underway for several decades, with much of the early research focused on creating visual prostheses that could replace damaged retinas in humans. But in recent years, there’s been growing recognition that the efficient and adaptable way in which the eye processes information could prove useful in applications where speed, flexibility, and power constraints are major concerns. Among these are robotics and the Internet of things.

Now, a pair of new research papers describe significant strides toward replicating some of the eye’s capabilities by more closely imitating the function of the retina—the collection of photoreceptors and neurons at the back of the eye responsible for converting light into visual signals for the brain. “It’s a very exciting extension from where we were before,” says Hongrui Jiang, a professor of engineering at the University of Wisconsin–Madison. “These two papers [explain research aimed at] trying to mimic the natural visual system’s performance, but on the retina level right at the signal-filtering and signal-processing stage.”

One of the most compelling reasons to do this is the retina’s efficiency. Most image sensors rely on components called photodiodes, which convert light into electricity, says Khaled Salama, professor of electrical and computer engineering at King Abdullah University of Science and Technology (KAUST), but photodiodes constantly consume electricity, even when they’re on standby, which leads to high energy use. In contrast, the photoreceptors in the retina are passive devices that convert incoming light into electrical signals that are then sent to the brain. In an effort to recreate this kind of passive light-sensing capability, Salama’s KAUST team turned to an electrical component that doesn’t need a constant source of power—the capacitor.

Leave a Reply

Your email address will not be published. Required fields are marked *