Persistence of Vision Display Kits

When a light moves quickly, it appears as a streak. Over a century ago, while swinging a lantern, Professor Lardner asked: "Do you really believe the lantern is in all those places at once?" The brain remembers an image for 1/10 of a second. This delayed response is called persistence of vision and explains how the images of movies, videos, and flip-books seem to blend together. The Mysterious Glowing Ball shows this concept perfectly with three LEDs that are red, green, and blue, but give the illusion that the ball is glowing white.