Flashing Dots
Grey lines on black, a white dot at every crossing — and black dots that flash where nothing black is drawn.
How to play
Look first, then answer
Grey lines on black, a white dot at every crossing — and black dots that flash where nothing black is drawn.
- Under a minute · one question · then the explanation
How it works — best read after you have tried it
Black dots that are never there
Every dot is white all the way through. Dark spots flash inside the dots you are not looking at directly, jump about as your eyes move, and are never in the one you look at.
The effect was found in 1994 by Elke Lingelbach, Bernd Lingelbach and Michael Schrauf, as a variant of the Hermann grid. It is much stronger than its ancestor and needs the grey lines: take them away and the dots are just dots.