During a livestreamed presentation on Tuesday, Professor Fan Zhiyong was holding something that looked like a circuit board with dozens of wires sticking out. But the most important part was the silver sphere sitting on top of the wiry contraption—a bionic eye.
The device developed by researchers at the Hong Kong University of Science and Technology (HKUST) is the first to replicate the structure of a human eye. And in the future, it might do more than restore sight to the vision impaired. It could also give us superhuman powers like night vision, Fan said.
Along with another professor named Gu Leilei, Fan leads the team at the university’s Department of Electronic and Computer Engineering, where they developed what they call the Electrochemical Eye (EC-Eye). It includes the first 3D artificial retina, according to the scientists. The research, which was published in the scientific journal Nature in May, has been hailed as a breakthrough.
The eye is one of our most complex organs. In real eyes, the retina is the thin layer of tissue that receives light and converts it into neural signals, sending it to our brains so it can be interpreted as an image. The bionic eye imitates this with an artificial retina using nanowire light sensors.
During the trial, the team connected the nanowire sensors to a bundle of liquid-metal wires that served as “nerves.” Those nerves replicated the image that the eye saw on the “brain”—a computer screen.
But to say the bionic eye simply replicates human eyes wouldn’t be entirely accurate. Vertebrates like humans have a blind spot in our eyes. Fan and Gu actually sought to improve on evolution by modeling their artificial retina on one without any blind spots. And for that they had to look to the ocean.
“We learned from two creatures,” Fan said. “[We used] our own and octopus eyes to improve the bionic structure.”
Although scientists have thought about creating bionic eyes for decades, only one prosthetic retina has been approved for human trials so far. It’s called the Argus II, and it was created by the US company Second Sight.
The device doesn’t make the wearer see in a way most of us are used to. Instead, it gives a narrow field of view, comparable to the size of a vertical screen on a smartphone. It also only allows for black-and-white images without fine details.
An even bigger obstacle is size. The Argus II uses a micro needle implanted within the eye and connected with a cable, requiring users to wear a bulky pair of glasses connected by wire to a remote control housing a battery. Because it sticks directly on the eye, the prosthetic isn’t comfortable, Fan said.
Along with scientists from the University of California, Berkeley, Fan and his team believe that wires won’t be necessary in the future. The implant could instead be self-powered through an electrochemical process similar to a type of solar cell.
The ambitions don’t stop there. While showing an image from the movie Terminator, Fan said he has always been a fan of science fiction. Whether it’s implanted in a robot or a human, the bionic eye could one day even exceed the capabilities of human eyes, he explained.
“In the future, we will be able to see even infrared, and if we can see infrared, we can have night vision,” Fan said.
The artificial retina may also offer higher image resolution than the human retina. Using different materials, scientists could boost the sensors’ sensitivity and spectral range.
But for now, these kinds of capabilities remain a distant dream. Scientists still have to figure out how to remove all the wires hanging from the silver sphere that might one day go inside our eyes. And while the eye can already see more infrared light than human eyes, its field of view is narrower.
Getting higher resolution images will also take some work. A demonstration video for the bionic eye played during the presentation showed a pixelated image that looked more like an old computer game.
As the scientists themselves noted, the device has a long way to go to catch up with human eyes. But they did offer a hint of when we might see people start to use this thing: The first clinical trials could start in five years, they said.