When it comes to the electromagnetic spectrum, humans are mostly in the (figurative) dark. We’re only able to perceive directly a thin slice — the visible spectrum of light. But technology lets us sense indirectly a much wider spectrum, including infrared waves. And now some engineers have come up with a room-temperature light detector that could lead to heat vision contact lenses.
The engineers started with graphene, which we’ve talked about a few times on Fw:Thinking. Graphene is a one-atom-thick sheet of carbon. It has some pretty phenomenal properties, including the ability to detect the full spectrum of infrared waves (plus visible and ultraviolet light). But it’s not very sensitive — graphene generates a very weak electrical signal when photons hit it. It’s typically so weak that it couldn’t be put to a practical use — night vision tech wouldn’t pull enough juice to work properly.
University of Michigan students and faculty looked into ways to increase the electrical signal to make graphene a viable heat vision technology. Using a material that’s just one atom thick would mean that thousands of potential applications would pop up — including those science fiction contact lenses.
Their solution was pretty darn cool. They didn’t try to monitor the electrons that escaped after photons collided with the graphene. Instead, they generated a current and watched how the current itself changed as graphene detected light. The escaping electrons affected the current and those changes became the signal that the engineers used to translate it into night vision. It sort of reminds me of how electric guitars convert magnetic fluctuations generated by vibrating strings into electrical signals.
I imagine we’ll see this technology added to devices like smartphones and augmented-reality glasses. Maybe we’ll even see contact lenses. Would you purchase a pair of heat-vision contacts?