Personal HUD comes closer with contact lens LED prototype

By David M Williams
Monday, 16 November 2009 06:38

Science - Biology

Researchers have produced a prototype contact lens that displays graphics, senses body chemistry information from the eye, and is powered by radio waves. Augmented reality, navigation and prick-free diabetes testing are all possible applications.

Babak Parviz at the University of Washington, Seattle, has constructed a revolutionary prototype device which can display information right before the eyes – literally – of its wearer.

Parviz had the idea that images could be projected into the eye from a contact lens and eradicate the problems faced by current mobile devices and heads up devices (HUDs), namely small display sizes and limited fields of view.

By contrast, Parviz’s lens can be as tall and wide as the eye can see, and ultimately with images that effectively float in front of the user perhaps 50cm to 1m away.

This work has not been without massive challenges. Fitting a contact lens with circuitry was a complex matter. The circuitry had to be transparent so as not to annoy the wearer, just to start with. Another problem was that the polymer material used by the contact lens could not withstand the temperatures or chemicals used in large-scale microfabrication so alternative designs had to be made.

The team also had to ponder over just how they could supply the 330 microwatts of power the device requires. Parviz solved this by equipping a loop antenna which picks up power beamed from nearby radio sources.

Future versions of the lens will harvest power from mobile phones, perhaps as they beam information to the lens, like the time and date, the identity of callers, maps and other information.

Other applications Parviz envisions are subtitles when conversing with foreign language speakers, captioned photographs, displays for pilots and for gamers, and many medical uses.

One immediate benefit of the contact lens is that it spends hours in contact with the human body and researchers are keen to explore the depth and breadth of information attainable this way. One immediate possibility, they believe, is that diabetics can monitor their blood sugar levels without having to prick fingers. Instead the lens will sample the information gleaned from the eye’s surface and display the results in front of the eye.

The future of the project is very exciting, but it will still be many years before any commercially-available implementation of the contact lens becomes viable, Parviz said.