Optical or Visual Illusions, Study notes of Human-Computer Interaction Design

Download Optical or Visual Illusions and more Study notes Human-Computer Interaction Design in PDF only on Docsity!

 Optical illusions are sometimes referred to as

visual illusions.

 They refer to objects or stimuli whose visual

interpretation differs from reality.

 Let us look at some examples.

1. Muller-Lyer illusion  (^) Consider the following figure:  (^) Which line is longer?  (^) The left line (i) seems longer than line (ii).  (^) However, the two lines are of the same length.

3. Ebbinghaus illusion (or Titchener circles)  (^) Consider the following figure:  (^) Which orange circle is bigger?  (^) The orange circle on the right seems bigger.  (^) However, the two orange circles are of the same size.

4. Ehrenstein illusion  (^) Consider the following figure:  (^) The sides of the square placed inside the pattern of concentric circles seem to take a curved shape.  (^) However, the sides are straight lines of a square.

 (^) Note that there are many other optical illusions.  (^) For instance: Silhouette illusion, Fraser spiral illusion, Hering illusion, etc.