3D Schröder Staircase Posted on 2020/12/18 by Carl Robitaille The Japanese master of optical illusions, Kokichi Sugihara, has won the 2020 Illusion of the Year with a 3D version of a well known 2D illusionhttps://t.co/JsXMnByXtH— Alex Bellos (@alexbellos) December 18, 2020