A new technology using natural electrical signals produced by human eye movements had led to the development of a robotic contact lens that can zoom in distant objects.

The new type of contact lens that utilizes soft robotics was developed by researchers from the University of California San Diego (UCSD). The development was detailed in a study published in the peer-reviewed scientific journal, Advanced Functional Materials.

The new technology is unlike those traditionally used to develop other soft robots. Soft robots are a type of robot made from materials that can twist and bend, which are either controlled manually or by algorithms.

UCSD researchers measured the electrooculographic signals generated by human eye movements. They then made a type of biometric contact lens that responds to normal eye behavior. This behavior included moving up and down or from side to side and blinking.

A person blinking twice in succession will cause the special lenses to change their focal length. This will allow the lens to zoom in and out just like users do on their phones. Because the lenses depend on electrical signals, they should function even if a person is blind. This advantage will prove very useful in helping to create visual prostheses.

“Even if your eye cannot see anything, many people can still move their eyeball and generate this electrooculographic signal,” lead researcher Shengqiang Cai said.

The lens is made from polymers that expand when electric current is applied. It’s controlled using five electrodes surrounding the eye. These electrodes act like human muscles. When the polymer becomes more convex, the lens effectively zooms in.

Researchers hope this technology will one day help create a prosthetic eye or a camera that can be controlled using the eyes alone.

“The system developed in the current study has the potential to be used in visual prostheses, adjustable glasses, and remotely operated robotics in the future,” said the study.

Human eye
The human eye, researchers found, is able to distinguish between remarkably subtle thicknesses due to its sharp color vision. Photo courtesy of