This display demonstrates the strobe light's ability to create optical illusions and to enable people to see images that occur too fast for the human eye to discern.
The main disc contains a variety of circular patterns. When you press and hold the button in, the disc spins and the strobe light goes on. By turning the knob you can adjust the frequency of the strobe light to see some interesting effects. Amongst other things, you should be able to make the disc appear as if it is not spinning at all, as if it is spinning in the opposite direction it is actually spinning in, and as if the dots are stationary but oscillating.