You've seen it in that spy show on TV, or that crazy sci-fi movie you watched last month: The dashing hero places a contact lens over his eye before setting off to infiltrate the bad guy's secret lair. As he sneaks past guards and cameras, his compatriots are sending him the path to follow, displayed through the tiny lens.
On a more practical note, such technology could be used to display subtitles to help you understand a foreign language, for example, or serve as a display for pilots.
New Scientist reports that these sci-fi lenses are getting closer to real life. A team from the University of Washington has developed a prototype lens that is designed to display information transmitted from a cell phone.
Fitting a contact lens with circuitry is challenging. The polymer cannot withstand the temperatures or chemicals used in large-scale microfabrication, Parviz explains. So, some components – the power-harvesting circuitry and the micro light-emitting diode – had to be made separately, encased in a biocompatible material and then placed into crevices carved into the lens.
One obvious problem is powering such a device. The circuitry requires 330 microwatts but doesn't need a battery. Instead, a loop antenna picks up power beamed from a nearby radio source. The team has tested the lens by fitting it to a rabbit.
Parviz says that future versions will be able to harvest power from a user's cell phone, perhaps as it beams information to the lens. They will also have more pixels and an array of microlenses to focus the image so that it appears suspended in front of the wearer's eyes.