Optical Illusions

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Optical Illusions
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Optical Illusions

• An optical illusion (also called a visual
  illusion) is characterized by visually perceived
  images that differ from objective reality. What
  are "illusions"? Illusions trick us into
  perceiving something differently than it actually
  exists, so what we see does not correspond to
  physical reality. Hence, the word illusion comes
  from the Latin verb illudere meaning, "to mock."
  In addition, some illusions show us one thing in
  a picture, while someone else sees something
  entirely different in the same picture.

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Optical Illusions

• Research scientists must be sure that the results
  of their work are not "illusory" in nature. They
  need to accurately report what "is", rather than
  their general "impression" of "what is". So many
  times a scientist will repeat an experiment many
  times, or in different laboratories, to ensure
  that their results were valid. Science is only
  "good science" when anyone can repeat the
  experiment and get the same results.

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So, lets take a look at some examples of
optical illusions.
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The red squares are the same color in the upper
part and in the lower part of the "X"
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The diagonal lines are parallel.
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There are no gray spots at the corners of the
squares.
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The center circles are both the same size.
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There are only white circles at the intersections

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Wavy Squares? No! The background of concentric
circles makes the squares appear distorted.
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Rotating Wheels The circles appear to rotate
when you move your head closer and further away
from the screen while looking at the dot in the
center.
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Warped Square? There are no curved lines in this
figure.
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• So never make a decision
• based
• on your observations