Optical illusion devices are tools or equipment designed to create visual phenomena that deceive the human eye’s perception of reality. These devices exploit the brain’s interpretation mechanisms, leading to a perceived image that differs from reality. Central to optical illusions are principles from cognitive psychology, neurobiology, and optical physics. Examples of optical illusions include the stereoscope which presents a different image to each eye to simulate depth perception; and the zoetrope which creates the illusion of motion through rapid sequence imagery. Optical illusions have been around for centuries, serving both magic, entertainment, and scientific purposes. Optical illusions played a role in developing early film and animation techniques and continue to shape virtual reality technologies today. The study of optical illusions provides understanding into human vision and perceptual processes.