The strong black and white contrast in this optical illusion tempts the eye to focus either only on the dark or only on the light part.
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The Ebbinghaus illusion is an optical illusion of relative size perception. Two circles of identical size are placed close to each other. One circle is surrounded by a ring of smaller circles, the other by a ring of larger circles. In the first case, this makes the middle circle appear larger, in the second case smaller.

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The Penrose Triangle, also known as the Tribar, is an impossible object first created by Swedish artist Oscar Reutersvärd in 1934. The mathematician Roger Penrose, who gave the object its name, independently developed and popularised this figure in the 1950s. This figure appears particularly frequently in the artworks of M.C. Escher.
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This graphic is an optical illusion that demonstrates how the human eye adapts to the perception of colour on different backgrounds. On the light grey background, the pink-coloured...

The so-called Müller-Lyer illusion is an optical illusion consisting of a stylised arrow. If you look for the centre of the arrow line, you usually place it more towards the rear end. This optical...

The systematically arranged lines in the picture create the perception of circles that are not actually there. The strokes are arranged in such a way that they create a circular field in their...

Sander's parallelogram is an optical illusion named after the German psychologist Friedrich Sander (1889-1971) in 1926. However, Sander was not the discoverer of this illusion, as it was already discovered in 1922....

The chessboard illusion is an optical illusion that was published by Professor Edward H. Adelson in 1995. The image shows a chessboard pattern with light and dark squares. The...

This optical illusion illustrates that the same luminance can be perceived with different brightness depending on the luminance of the surrounding objects. The grey rectangles shown all have the same luminance. The rectangles,...