A copy of Fraser's spiral A copy of Fraser's spiral
Access since April 28, 2008
The term "spiral illusion" had long referred to the spiral illusion of the Fraser illusion (Fraser, 1908) before we elucidated that any tilt illusion can form spiral illusion (Kitaoka, Pinna and Brelstaff, 2001). This page shows a copy of Fraser's spiral produced by PC programming.
<August 30, 2003>
Another copy was produced with CorelDRAW. <January 7, 2009>
Another simpler copy was produced with CorelDRAW. <April 17, 2010> new!
Fraser, J. (1908) A new visual illusion of direction. British Journal of Psychology, 2, 307-320.
new!
First presented by Fraser (1908); Reproduced by Akiyoshi Kitaoka (2009)
Large bitmap 
updated!
Adobe Illustrator file (version 8) new!
First presented by Fraser (1908); Reproduced by Akiyoshi Kitaoka (2008)
First presented by Fraser (1908); Reproduced by Akiyoshi Kitaoka (2003)
First presented by Fraser (1908); Reproduced by Akiyoshi Kitaoka (May 19, 2015)
First presented by Fraser (1908); Reproduced by Akiyoshi Kitaoka (May 19, 2015)
First presented by Fraser (1908); Reproduced by Akiyoshi Kitaoka (2010)
Mar 20, 2010
How to make a simple version of the spiral illusion of the Fraser illusion
Copyright Akiyoshi Kitaoka 2012 (November 14)
Copyright Akiyoshi Kitaoka 2013 (January 28)
Copyright Akiyoshi Kitaoka 2016 (June 28)
An instance of the Fraser spiral illusion: Concentric circles appear to be spirals. pic.twitter.com/x5RBwla9UF
— Akiyoshi Kitaoka (@AkiyoshiKitaoka) 2018”N2ŒŽ12“ú