Optical illusion There are a variety of different types of optical illusions. Many are included in the following list. Artists who have worked with optical illusions include M. C. Escher, Bridget Riley, Salvador Dalí, Giuseppe Arcimboldo, Patrick Bokanowski, Marcel Duchamp, Jasper Johns, Oscar Reutersvärd, Victor Vasarely and Charles Allan Gilbert. Contemporary artists who have experimented with illusions include Jonty Hurwitz, Sandro del Prete, Octavio Ocampo, Dick Termes, Shigeo Fukuda, Patrick Hughes, István Orosz, Rob Gonsalves, Gianni A. Sarcone, Ben Heine and Akiyoshi Kitaoka. Optical illusion is also used in film by the technique of forced perspective. Op art is a style of
Zöllner illusion Zöllner illusion The Zöllner illusion is an optical illusion named after its discoverer, German astrophysicist Johann Karl Friedrich Zöllner. In 1860, Zöllner sent his discovery in a letter to physicist and scholar Johann Christian Poggendorff, editor of "Annalen der Physik und Chemie", who subsequently discovered the related Poggendorff illusion in Zöllner's original drawing. One depiction of the illusion consists of a series of parallel, black diagonal lines which are crossed with short, repeating lines, the direction of the crossing lines alternating between horizontal and vertical. This creates the illusion that the black lines are not parallel. The shorter lines are