Stereopticon is an antique device that projects two-dimensional images onto a screen using a combination of lenses and mirrors. This old-fashioned gadget has been replaced by modern-day projectors and digital screens, but its legacy still lives on. Some of the synonyms for Stereopticon include Magic Lantern, Optical Lantern, View-Master, and Projector. Each of these terms refers to devices that use similar mechanisms to project images and video onto a screen or wall. Magic lanterns were especially popular in the 1800s and early 1900s, while View-Masters became popular in the mid-20th century. Today, projectors are the most common device used to project images and videos onto a screen.