Akiyoshi Kitaoka, a professor of psychology at Ritsumeikan University in Osaka, Japan, is known for his research on visual perception and illusions. His website features an extensive collection of illusion images, including “anomalous motion illusions” that may cause dizziness or discomfort for some viewers. Kitaoka’s illusions range from rotating snakes and rays to images that appear to move or wave. He also explores color illusions, shape illusions, and spatial illusions. Commercial use of his images is prohibited, and permission must be obtained for educational or research purposes. Overall, the website offers a wide range of unique and intriguing optical illusions.
https://www.ritsumei.ac.jp/~akitaoka/index-e.html