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KRAVETS

                                                   Optical illusions

An optical illusion (also called a visual illusion) is 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 illusions that are the effects of excessive stimulation of a specific type (brightness, colour, size, position, tilt, movement), andcognitive illusions, the result of unconscious inferences. Pathological visual illusions arise from a pathological exaggeration in physiologicalvisual perception mechanisms causing the aforementioned types of illusions. 

 All depending on their origin can be divided optical illusions into 3 types:

1. Natural (created by the nature) – a Mirage.

1. Artificial (thought up by the person). This type is used often by conjurers-illusionists. Such illusions have a constructive secret and the explained mechanism of occurrence and action.

1. Mixed (natural illusions which were recreated by the person) is and model of a Mirage, and pictures.

EXAMPLES :

1

 If your eyes follow the movement of the rotating pink dot,
the dots will remain only one color, pink. 

However if you stare at the black " +" in the center, the moving dots turns to green.

2

 Your eyes are making them move.

3

There are some types of occurrence of optical illusions - optical deceits which for not at all studied reasons the nature (has created the most known example are Mirages in deserts) 

Example widely known optical focus - soaring in air (levitation) serves. Illusions recreated by the person on known natural deceits mixed optical illusions -  illusions visual pictures are not less interesting are.  

 End little questions  about illusions

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