Slide projector

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Slide projector" – news · newspapers · books · scholar · JSTOR (September 2022) (Learn how and when to remove this message)

A slide projector is an optical device for projecting enlarged images of photographic slides onto a screen. Many projectors have mechanical arrangements to show a series of slides loaded into a special tray sequentially.

35 mm slide projectors, direct descendants of the larger-format magic lantern, first came into widespread use during the 1950s for slide shows as home entertainment, and for use by educational and other institutes. Reversal film created a small positive projectable image rather than the negatives used since the early days of photography; photography now produced 35mm directly viewable small colour slides, rather than large monochrome negatives. The slide images were too small for unaided viewing, and required enlargement by a projector or enlarging viewer.

Photographic film slides and projectors have been replaced by image files on digital storage media shown on a projection screen by using a video projector, or displayed on a large-screen video monitor.