New Type Of Eye Implant Could Help Blind People See Again

Scientists have created a new type of eye implant that could help blind people see again. Made from a special material called tellurium, the device transforms light, including infrared light, which the human eye normally cannot see, into signals that the brain can understand. It has been successfully tested in mice and monkeys, improving their response to light without the need for batteries or external devices. This technology could eventually restore vision to people with serious eye diseases.

In nature, some animals, such as snakes and foxes, can see their surroundings better because they can capture both visible light and infrared light, a type of light that human eyes cannot perceive.

This is because our eyes do not have sensors capable of detecting this type of light, which has less energy and does not activate our visual system. However, in people with serious eye diseases, such as macular degeneration, the ability to see in infrared light could be very helpful, especially in dark or low-light environments.

Therefore, creating technologies that allow us to see not only ordinary light, but also infrared, can bring great advances for those with vision loss.

Scientists are developing eye implants to help people who are blind or visually impaired regain their vision. In this study, researchers at Fudan University in Shanghai have created a new type of retinal prosthesis, a device that replaces part of the eye’s function using a special material called tellurium, arranged in microscopic strands called nanowires.

This material has the ability to transform light, both visible and infrared (such as that used in remote controls or night vision), into electrical signals, which can be used to stimulate the eye and send information to the brain.

One of the main challenges in creating ocular prosthetics is that they usually require batteries or external equipment to function. This new device, however, does not require an external power source; it directly harnesses ambient light.

In addition, it can capture a wider range of light than human eyes can normally, including infrared light. This means that, in addition to restoring normal vision, it could allow a person to “see in the dark,” something that would be especially useful for those who have lost photoreceptors (the cells in the eye that capture light).

Tellurium Nanowires

To understand how this device works, scientists first conducted theoretical and laboratory tests to analyze how tellurium nanowires react to light. They discovered that, due to the way the wires were organized and the characteristics of the material, it was possible to generate very strong electrical signals when receiving light, including infrared light, which is normally not perceived by human eyes.

Then, they conducted practical tests on blind mice. They implanted the device in a specific region behind the eye, called the subretinal space. This place was chosen because it is where damaged photoreceptors normally are, and the device would serve precisely to replace them.

After the implant, scientists observed how the mice's brains reacted to light. And the results were encouraging: the animals returned to showing normal reactions to light, such as pupil contraction. 

Behavioral tests were also performed, such as learning to identify which box contained water when shown a light signal. The mice with the implant learned much faster than those without the device, even at very low light levels, about 80 times lower than the limits considered safe for humans.

The tests were then performed on monkeys (Macaca fascicularis), which have eyes more similar to those of humans. The device was safely implanted, attached well to the retina and responded to both visible and infrared light stimuli, showing that it can also work in more complex organisms.

A next-generation nanoprosthesis that restores and enhances vision. Tellurium has a broad spectrum of optical absorption, from visible to infrared light (top left). A subretinally implanted tellurium nanoprosthesis replaces degenerated photoreceptors and generates photocurrents that convert this light into electrical signals, which are sent through the retina (bottom left) to the brain in the occipital cortex (top right), where they are interpreted as images. Giant, spontaneous, and unbiased photocurrents and minimally invasive implantation are achieved through engineering the asymmetry and morphology of the nanowire network (bottom right). Together, these properties make tellurium nanowire networks (TeNWNs) the next generation of visual prosthesis technology.

This study has shown that it is possible to create a retinal prosthesis that captures visible and infrared light and converts this light into electrical signals capable of activating the visual nerves and sending information to the brain. The implant is small, biocompatible (i.e., it does not cause rejection) and does not require batteries or external wires.

In addition to restoring normal vision, it can allow blind people to have access to a new form of vision in the dark, something never before seen.

Although the tests were carried out on animals, the results are very promising for helping visually impaired humans to see again in the future, with a safer and more effective solution than those currently available.

READ MORE:

Tellurium nanowire retinal nanoprosthesis improves vision in models of blindness

SHUIYUAN WANG, CHENGYONG JIANG, YIYE YU, ZHENHAN ZHANG, RUGE QUHE, RUYI YANG, YUFEI TIAN, XINDONG CHEN, WENQIANG FAN, 

YINGE NIU, BIAO YAN, CHUNHUI JIANG, YANG WANG, ZHEN WANG, CHUNSEN LIU, WEIDA HU, JIAYI ZHANG, AND PENG ZHOU 

SCIENCE, 5 Jun 2025, Vol 388, Issue 6751

DOI: 10.1126/science.adu2987

Abstract:

Present vision restoration technologies have substantial constraints that limit their application in the clinical setting. In this work, we fabricated a subretinal nanoprosthesis using tellurium nanowire networks (TeNWNs) that converts light of both the visible and near-infrared–II spectra into electrical signals. The broad-spectrum coverage is made possible by a combination of narrow bandgaps, strong absorption, and engineered asymmetries. Implanted into blind mice, the TeNWNs restored pupillary reflexes and enabled visually cued learning under visible and near-infrared 1550-nanometer light. In nonhuman primates, TeNWNs elicited robust retina-derived neural responses, confirming biocompatibility and feasibility. By restoring lost photosensitivity and extending vision to near-infrared, this nanoprosthesis offers a promising approach for restoring vision.