Smart glasses let you turn off the lights in the blink of an eye

A pair of glasses that can harness the movement around your eye when you blink could be used to manipulate the world around you

Blink and the lights go out. A sensor on a pair of glasses that can pick up the motion of your skin when you blink could be used to switch the lights on and off, or to help those with limited or no mobility write messages on a computer.

“The good thing about the technology is the high sensitivity, which may become particularly useful in places where the motion is very limited,” says Ambarish Ghosh at the Indian Institute of Science, who wasn’t involved in the research.

The sensor, called a triboelectric generator, is thin enough to fit on the arms of a pair of glasses. It is made from multiple polymer layers with a coating of metal that acts as an electrode. Each time someone blinks, the motion of skin to the side of the eye causes the polymer layers to touch and release, generating an electrical signal. One, two or three consecutive blinks can be used to scroll through the alphabet to spell out a message on a computer, for example.

This signal can be transmitted through a wire or wirelessly, leading to the potential hands-free operation of various appliances, including cellphones. It could also aid people who have limited or no mobility of limbs because of accidents or conditions such as Lou Gehrig’s disease.

The glasses were created by Zhong Lin Wang at the Georgia Institute of Technology and his colleagues at the Chinese Academy of Sciences in Beijing. They first demonstrated the principle of harvesting energy using the triboelectric effect in 2013.

However, blinking is involuntary, and unless you enjoy a disco effect, it may turn appliances off and on when you don’t want them to. “You can set a threshold for the switch,” says Wang. Only when the signal is higher than the threshold, which means you really have to blink hard, can the switch be triggered.

This could be useful in many different applications, says Ghosh, such as using the motion of other muscles or in systems that may require constant monitoring, both biological and non-biological.

The team now plans to use the sensor on other parts of the body to explore its potential in intelligent robotics applications. Wang says that if they can improve the level of the signal generated, the entire system can be self-powered.