Google reveals smart contact lens prototype designed to aid diabetics

Google unveils a contact lens that monitors glucose levels in tears, something millions of diabetics currently have to draw their own blood to check.

The lenses use a minuscule glucose sensor and a wireless transmitter to help those among the world's 382m diabetics who need insulin keep a close watch on their blood sugar and adjust their dose.

The prototype, which Google says will take at least five years to reach consumers, is one of several medical devices being designed by companies to make glucose monitoring for diabetic patients more convenient and less invasive than the traditional blood-drawing finger pricks.

"We're testing a smart contact lens that we built that measures the glucose levels in tears using a tiny wireless chip and a miniaturised glucose sensor," explained the Google X project leader for the smart contact lens, Brian Otis.

The device, which looks like a typical contact lens, contains two twinkling glitter-specks that are loaded with tens of thousands of miniaturised transistors and is ringed with a hair-thin antenna.

"We've had to work really hard to develop tiny, low-powered electronics that operate on low levels of energy and really small glucose sensors," Mr Otis said at Google's Silicon Valley headquarters.