Presentation Transcript
Optical Illusions: Optical Illusions Matt Gray
What is an optical illusion?: What is an optical illusion? a type of illusion characterized by visually perceived images that are deceptive or misleading our visual systems adapt to standard viewing situations eye cannot see, it merely perceives information “Illusions of the senses tell us the truth
about perception”
Categories of Illusions: Categories of Illusions physiological illusions
occur naturally
brain is not tricked
perception not a factor
example: after images cognitive illusions
visual tricks
misdirects visual system’s adaptations to common situations
the majority of optical illusions
Checker Shadow Illusion: Checker Shadow Illusion Based on the position of squares relative to surrounding colors the eye percepts them to be different
The light square in shadow is surrounded by darker square’s also in shadow
Thus, even though the square is physically dark, it is light when compared to its neighbors
More Context Illusions: More Context Illusions
Face Mask Illusion:
Face Mask Illusion one cannot ‘hold’ either the positive or negative view The hollow (negative) version of the face immediately switches back into a positive view
Impossible Objects: Impossible Objects
Size Constancy Illusions: Size Constancy Illusions perception of size constancy depends on cues that allow one a valid assessment of his distance from the object
we see objects as the same size at different distances because they stay the same size relative to surrounding objects
The monkey example gives the information that they are the same size but that one monkey is farther away from the other, thus the further one must be larger Click picture
Motion Perception: Motion Perception
Café Wall Illusion : Café Wall Illusion The mortar lines (the horizontal lines between the tiles) appear to slope alternately upward and downward This gives the impression that the tiles are wedge-shaped. Horizontal lines are ACTUALLY
all parallel
Works Cited: Works Cited 61 Optical Illusions & Visual Phenomena. Michael Bach. http://www.michaelbach.de/ot/ Optical Illusions. Multiple Authors. http://www.sapdesignguild.org/resources/opticali llusions/optical_illusions.pdf#18 Optical Illusion. Wikipedia, the free encyclopedia. http://en.wikipedia.org/wiki/Optical_illusions The Eye Beguiled, Optical Illusions. Bruno Ernst. © 1986 Bruno Ernst. Produced in Germany.
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