As much as we think our eye movements are smooth, they are actually very erratic. Constantly darting all around our surroundings, trying to take in as much as possible.
This makes something like writing with your eyesight extremely difficult. Until now.
A French neuroscientist has harnessed the power of an optical illusion to focus our gaze, therefore allowing for smooth movements. With this breakthrough, writing with only your eyes could be a reality for many disabled people.
It utilizes “reverse phi motion.”
Phi motion is essentially the effect that turns a series of still photos into a movie, but reverse phi motion is a bit weirder. Take a film of a moving white dot then turn the dot in every other frame black, and the film will appear to run backwards – that’s reverse phi in action.
Lorenceau’s system uses a display covered in dots that flick from all-white to all-black. The reverse phi illusion means that moving your eye in any direction while looking at the screen makes it appear as if an on-screen dot is moving in that same direction.
Check out a reverse phi motion demonstration below. What you are seeing is two frames from a documentary, however, because of the change from white to black we assume there is motion. This tricks our eyes into focusing on it.