3D printed light receptors hold promise in development of bionic eyes

Researchers from the University of Minnesota started with a hemispherical glass dome to show how they could overcome the challenge of printing electronics on a curved surface.

Using a custom-built 3D printer, they started with a base ink of silver particles. The dispensed ink remained in place and dried uniformly instead of running down the curved surface. The researchers then used semiconducting polymer materials to print photodiodes, which convert light into electricity. The entire process - seen below - is said to take about an hour.

"Bionic eyes are usually thought of as science fiction, but now we are closer than ever using a multimaterial 3D printer," said Michael McAlpine, a co-author of the study published in Advanced Materials, and University of Minnesota Benjamin Mayhugh Associate Professor of Mechanical Engineering.

McAlpine said the most surprising part of the process was the 25 per cent efficiency in converting the light into electricity they achieved with the fully 3D printed semiconductors.