Magic lantern

A magic lantern is an optical projection device that projects images painted or photographed on transparent glass slides onto a screen by means of a light source and a lens system. Developed in the 17th century, it functioned as an early form of image projection for education, entertainment, and public lectures.

Stereoscopy and magic lanterns were popular at approximately the same time, in the late 19th and early 20th centuries, during the period preceding the emergence of cinema. Publishers of stereoviews often produced corresponding magic lantern slides, using half-stereo images derived from one side of a stereo negative. In this way, the same photographic source material could serve both stereoscopic viewing and projected presentation.