Phantogram (optical illusion)

Phantograms use perspectival anamorphosis to produce a 2D image that is distorted in a particular way so as to appear, to a viewer at a particular vantage point, three-dimensional, standing above or recessed into a flat surface.

Contemporary artists such as Kurt Wenner and Julian Beever use similar techniques to create chalk pavement art that appears to be three-dimensional.

Similar effects are often seen on televised sporting events, where sponsor logos are painted onto the playing field or track, distorted so as to appear "upright" from the viewpoint of a particular TV camera.

Numerous patents similar to Macy's 1926 application have been filed, refining the process and detailing different techniques and devices for creating phantograms (Woods, Marjorie (1988); Western, Owen (2002); Aubrey, Steve (2003)).

Western and Aubrey registered trademarks for the images resulting from their processes; "Phantaglyph" and "Op-Up" respectively.

The pair of images used to create a phantogram are anamorphic projections of a solid object onto a flat surface (using photographs of a real object, or drawings/computer-generated images).