This Line of Light is Actually An Image.
There’s an image hidden in this flickering line of light. You just have to shake your head to see it.
Created by Bill Bell, the Triple Aye Light Stick uses a loophole in your vision system called persistence of vision. The human eye and brain process only 10 to 12 separate images per second. But they retain them for just slightly shorter: up to a fifteenth of a second. Moving the head back and forth puts this line across the back of the eye multiple times. For every line, the eye and brain hold—or save—the image briefly. With each snapshot saved, the lines become a full image.
This was created in collaboration with Exploratorium. The Exploratorium is an interactive museum on San Francisco’s waterfront, a professional-development home for teachers, and an exhibit-design trailblazer with a mission to transform learning worldwide.
