Tech Primer

Contact Lens Display System

Display and computer vision are areas wherein researchers keep coming up with new technologies. The University of Washington has come up with new technology called Contact lens Display System. It has implemented microscopic manufacturing or self-assembly (capillary forces) to make a new kind of hybrid contact. This contact lens has microscopic imprinted circuit with light emitting capabilities.

Usage

Characters in games and movies have been using bionic eyes to zoom in on far-off scenes, have useful facts pop into their field of view, or create virtual crosshairs. These can well be some of the uses to which this device can be put to but in real life virtual displays have been proposed for more practical purposes such as visual aids to help vision-impaired people, holographic driving control panels and even as a way to surf the Web on the go. Further, there are many other possible uses for virtual displays. Drivers or pilots could see a vehicle’s speed projected onto the windshield, and video-game companies could use the contact lenses to completely immerse players in a virtual world without restricting their range of motion.

Building the lens

The prototype contains an electric circuit as well as red light-emitting diodes for a display, though it does not light up as yet. The lenses were tested on rabbits for up to 20 minutes and the animals showed no adverse effects. Manufacturing techniques at microscopic scales have been used to combine a flexible, biologically safe contact lens with an imprinted electronic circuit and lights. The lenses were built using materials that are safe for use in the body, such as the flexible organic materials. Manufacturing electrical circuits involved inorganic materials, scorching temperatures and toxic chemicals. The circuits were made with the help of layers of metal which were only a few nanometers thick which is about one thousandth the width of a human hair, and constructed light-emitting diodes one third of a millimeter across. Grayish powder of electrical components was sprinkled onto a sheet of flexible plastic. A microfabrication technique was used for self assembly in which the shape of each tiny component dictates which piece it can attach to. Capillary forces—the same type of forces that make water move up a plant’s roots, and that cause the edge of a glass of water to curve upward—pull the pieces into position.

Scope

The prototype, as of now, is not able to correct the wearer’s vision, but the technique could be used on a corrective lens as well. Future improvements could add wireless communication to and from the lens. The whole system can be powered using a combination of radio-frequency power and solar cells placed on the lens. According to researchers, a full-fledged display will not be available for a while, but a version that has a basic display with just a few pixels could be operational quite soon.

For more information, visit:uwnews.washington.edu/ni/article.asp?articleID=39094

— Kushal Shah