Artificial eyes: a new hope for the blind

Artificial eyes

A new artificial eye could outperform human eyes. Researchers said the device mimics the human eye’s structure. This new device has a faster reaction time than a real eyeball. Researchers said that this electronic device does have the potential for sharper vision than human eyes. The human eyes get its wide field of view and high-resolution eyesight from the dome-shaped retina found at the back of the eyeball. The retina is covered in light-detecting cells or photosensors.

To mimic that architecture in their synthetic eyeball. Researchers used a curved aluminum oxide membrane covered with nanosize sensors made of a light-sensitive material called perovskite. Wires attached to the artificial retina send readouts from those sensors to external circuitry for processing. This is similar to nerve fibers relaying signals from a real eyeball to the brain. 

The artificial eyeball registers changes in lighting faster than human eyes. The new device has a speed of about 30 to 40 milliseconds compared to 40 to 150 milliseconds in a human eye. The new device can also see dim light just like the human eye. Its field of view (100 degrees) isn’t as wide as the human eye’s field of view (150 degrees). But it’s better than the 70 degrees filed found in ordinary flat imaging sensors.

This synthetic eye could perceive a much higher resolution than the human eye because it contains about 460 million light sensors per square centimeter. A human retina has about 10 million light-detecting cells per square centimeter but each sensor will require separate readings and connectivity. 

In the current device, each wire is about one millimeter thick so only 100 such wires fit across the back of the retina. This means that the synthetic eye can currently create images that have 100 pixels. But the team wants to prove that thinner wires could be connected and that the synthetic eye can provide a higher resolution. 

Therefore, they used a magnetic field to attache a small array of metal needles. Each needle is 20 to 100 micrometers thick. They were attached, one by one to nanosensors on the synthetic retina. The researchers said that their next challenge is to find a more efficient way to manufacture vast arrays of tiny wires