A teleprompter is a display device that prompts the person speaking with a visual text of a speech or script. The idea was conceived by the actor Irving Berlin Kahn (1917-1994) to assist television performers, and the first model was developed by Hubert Joseph "Hub" Schlafly Jr. (1919-2011) in 1950. However, this early model was simply a mechanical device, operated by a hidden technician, located near the camera. The script, in large letters, was printed by a special electric typewriter on a paper scroll, which was advanced as the performer read.

Jess Oppenheimer (1913-1988), the creator of the TV show “I Love Lucy”, made a major advance in the technology with the first "in-the-lens" prompter. This system uses a mirror to reflect a script onto a piece of glass placed in front of the camera lens, allowing the reader to look directly into the camera. It was used by the “I Love Lucy” actors Lucille Ball and Desi Arnaz in 1953 to read commercials on-camera.

Because the system means that the speaker can look straight at the lens while reading a script, the teleprompter can create the illusion that the speaker is talking spontaneously. Since there is no distraction from looking away at notes it is possible to connect directly with a TV audience. It is not surprising that this feature appeals to politicians.

On 4 January 1954 Dwight D. Eisenhower followed the lead taken on “I Love Lucy” and became the first US President to use a teleprompter for a State of the Union address.

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