Also called a "viewgraph," the overhead projector was created by Jules Duboscq, a French inventor, in the 1870s.[1] It was first used for police work, and used a cellophane roll over a 9-inch stage allowing facial characteristics to be rolled across the stage. The U.S. Army in 1945 was the first to use it in quantity for training as World War II wound down. It began to be widely used in schools and businesses in the late 1950s and early 1960s.
A major manufacturer of overhead projectors in this early period was the company 3M, where engineer Roger Appledorn had developed a transparency projection system.[2] As the demand for projectors grew, Buhl Industries was founded in 1953, and became the leading US contributor for several optical refinements for the overhead projector and its projection lens. In 1957, the United States' first Federal Aid to Education program stimulated overhead sales which remained high up to the late 1990s and into the 21st Century.