”Ben & Aki’s Christmas rings 2011”
The rings appear to rotate in the different direction from each other when observers approach or move away from the image fixing their eyes at the center. This illusion is called the Pinna illusion. Moreover, the outer ring appears to expand while the inner one appears to contract. This illusion depends on a variant of the Fraser-Wilcox illusion, which I call the ”optimized Fraser-Wilcox illusion, Type IIa”. In addition, the central Star of David is made up of two Penrose triangles. The basic idea of this illusion work was presented by Professor Ben Backus, SUNY.
Copyright Akiyoshi Kitaoka 2011 (December 26)