Orbison illusion

Orbison illusion consisting of a square placed over radial lines.

The Orbison illusion (or Orbison's illusion) is an optical illusion first described by American psychologist William Orbison (1912–1952)^[1] in 1939.

The illusion consists of a two-dimensional figure, such as a circle or square, superimposed over a background of radial lines or concentric circles. The result is an optical illusion in which both the figure and the rectangle which contains it appear distorted; in particular, squares appear slightly bulged, circles appear elliptical, and the containing rectangle appears tilted.^[2]

Further examples

• 
  Square distortion by concentric circles
• 
  Circle distortion by radial lines
• 
  Square distortion by beams

References

1. Roeckelein, Jon E. (2006). Elsevier's Dictionary of Psychological Theories. Amsterdam: Elsevier. p. 651. ISBN 9780444517500.
2. "Orbison illusion". opticalillusions.info. Archived from the original on October 7, 2016. Retrieved June 30, 2016.

• Fineman, Mark (1996). The Nature of Visual Illusion. Dover Publications. pp. 152-153. ISBN 0486291057.
• Robinson, J.O. (1998). The Psychology of Visual Illusion. Dover Publications. pp. 72–73. ISBN 978-0486404493.