Pulfrich Effect - Overview

Overview

The effect is generally induced by placing a dark filter over one eye but can also occur spontaneously in several eye diseases such as cataract, optic neuritis, or multiple sclerosis. In such cases, symptoms such as difficulties judging the paths of oncoming cars have been reported. The phenomenon is named for German physicist Carl Pulfrich, who first described it in 1922. The effect has been exploited as the basis for some television, film, and game 3D presentations.