Overhead projector
Videos
An overhead projector, like a film or slide projector, uses light to project an enlarged image on a screen, allowing the view of a small document or picture to be shared with a large audience.
Overhead projector in operation during a classroom lesson
Mirror and lens
A worker loads documents into an Ozalid printer.
Slide projector
Videos
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 specia
A 1960 slide projector
Continuous-Slide Lantern, c. 1881
A Kodak Carousel model 4400 slide projector, first sold in the mid-1980s
Self-contained slide projector with rear-projection screen and carousel tray