A few months ago, news broke of an amazing new image display system capable of projecting 3D images into thin air. Unlike practically every other projection system that's ever been invented, this technique doesn't need any sort of screen to bounce light back at your eyeballs. Instead, the display system uses a set of finely-tuned lasers to selectively ionize molecules in the air, which causes them to emit a bright white burst of light.
Pretty crazy, right? Well it gets even crazier. After a few months of tinkering with the design, the system's creators at Aerial Burton have taken it a step further, and have actually figured out a way to make the projected images touch-interactive. Seriously -- the world now has touchable in-air laser projection displays. It's only a matter of time before we have those rad Star Wars-style hologram generators built in to our phones.
As you'd expect, making these projected images touch-sensitive was no easy feat. The projection system basically works by focusing laser beams at specific points in the air, and heating up the gases so much that they ionize and create pockets of floating plasma -- which could potentially burn you if you touched them. Aerial Burton's first few prototypes were actually hot enough to burn leather, so the company needed to come up with a solution.
So how'd they make it safe? In a nutshell, they basically just turned up the speed at which the system's lasers pulse. Early versions pulsed in nanosecond bursts, which still contained a significant amount of energy. The new version, however, pulses in femtoseconds (1 nanosecond = 1,000,000 femtoseconds), which means the plasma bursts are shorter-lived but more frequent -- so they don't stay focused on a single area long enough to burn you.
It also happens that these plasma bursts tend to get brighter when they come into contact with a finger, so Aerial Burton devised a way to use this effect as an interaction cue. When you touch the projected image, the system now instantly recognizes it, and can be programmed to display a different image when touched.
As it turns out, you can actually feel the images when you touch them too. Tiny shock waves are generated by the plasma bursts when a user touches them, which are felt as an impulse on the finger -- almost like the light has physical substance to it.
Aerial Burton initially began developing this tech as a way to display signs in mid-air during emergency situations, but the potential applications go far beyond that. We can't wait for the day that this tech inevitably winds up in our pockets.