#152 : Straight Lines?

An optical illusion is the difference between reality and what the brain thinks its seeing. The information gathered by the eye is processed in the brain to give a image that does not agree with a physical measurement of the source. There are three main types: literal optical illusions that create images that are different from the objects that make them, physiological ones that are the effects on the eyes and brain of excessive stimulation of a specific type (brightness, tilt, colour, movement), and cognitive illusions where the eye and brain make unconscious inferences.

Our Favourites

Shadow Illusion Are the squares A and B the same colour?   Spinning Dancer Which way is the dancer spinning?   Impossible Waterfall? Is the water flowing uphill in this impossible waterfall?   The Butterfly A colourful butterfly?

Duck Or Rabbit? Is this a duck or a rabbit?   Hidden Faces Can you find his three daughters as well?   Blind Spot An amazing demonstration of your blind spot.   Impossible Prongs? Impossible prongs?

What Am I? Can you tell what this is a picture of?   Who Turned To? Who is missing?   Same Eyes? Are her eyes the same colour?   Parallel Cafe Wall Lines? Are the horizontal lines parallel?