An optical illusion is a picture or a figure that deceives or confuses the eye and/or brain. Categorization of optical illusions is difficult because several underlying mechanisms may contribute to an effect, or the cause of the illusions may not be completely understood. See individual entries in the table below for details. See also anamorphosis.
|Types and examples of optical illusions|
|distortion illusion||Fraser spiral
|impossible figures and objects||Freemish crate
|ambiguous figure||Ames room
Schröder's reversible staircase
|lateral inhibition illusion||Hermann grid illusion|
|antigravity houses and hills|