Bionics is usually the stuff of science fiction, but lately more sci-fi has been leaking into reality. With the aid of modern techniques, we’re developing custom organs and implants, and now eyes. Researchers from the University of Minnesota have made the most advanced prototype of a bionic eye yet, using an array of light receptors on a hemispherical surface. The could someday aid blind or visually-impaired people in recovering their sight.

While the research is still in its infancy, it is fascinating nonetheless. The researchers began with the hemispherical glass dome, developing a method for printing electronics on curved surfaces. They developed a custom 3D printer to print a base ink of silver particles that achieved this effect. When the ink stayed in place, drying evenly across the surface without streaking downwards, the researchers used semiconducting polymer materials to print photodiodes. The photodiodes convert light into electricity, the basic component for turning sight into usable signals.

Amazingly, this entire process takes about an hour. According to Michael McAlpine, a co-author of the study, the efficiency of the setup shocked even them. According to the researchers the 3D-printed semiconductors could maintain a 25 percent efficiency in converting light into electricity.

The next step in developing a functional eye will be to print one with far more photoreceptors. They would also need a much softer material so that it would blend with the human eye properly. This design could eventually serve as an implant that fits over the real eye. “We have a long way to go to routinely print active electronics reliably, but our 3D-printed semiconductors are now starting to show that they could potentially rival the efficiency of semiconducting devices fabricated in microfabrication facilities,” McAlpine said. “Plus, we can easily print a semiconducting device on a curved surface, and they can’t.” Bionic organs and parts have become somewhat of a niche field for these researchers. McAlpine’s team have previously worked on ears and skin as well. This new venture is probably the most advanced work they’ve engaged in, however. The team are no strangers to ground-breaking tech, but a functional bionic eye would outdo even their outstanding portfolio.