Introduction: The Refraction of Light in Water
Optical illusion (visual illusion) - error in visual perception caused by the inaccuracy or inadequacy of the processes unconscious correction of the visual image, as well as physical causes ( "flattened the Moon", "broken spoon" in a glass of water).
There is an effect of visual perception when the observer is consciously or unconsciously makes factually inaccurate explanation for the observed pattern to them.
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