Optical Illusions
An optical illusionis characterized by visually perceived images that differ from objective reality. The information gathered by the eye is processed in the brain to give a perception that does not tally with a physical measurement of the stimulus 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 , and cognitive illusions, the result of unconscious inferences.
Motion effect
In this Optical Illusion, if you stare at the center of the visually for several seconds and look at something else, some very strange will happen to your vision.
Kanizsa triangle
These spatially separate fragments give the impression a bright white triangle. The brain makes you see a triangle there, when in fact, there is none.
Simultaneous Contrast Illusion
Simultaneous Contrast Illusion. The background is a colour gradient and progresses from dark grey to light grey. The horizontal bar appears to progress from light grey to dark grey, but is in fact just one colour.
Revolving Circles
The two circles seem to move when the viewer's head is moving forwards and backwards while looking at the black dot.
Cafe Wall
The lines appear to be jagged and moving off to the side, however, the lines are straight. The alternating black and white squares make it seem to slant, creating the illusion.