How does a teleprompter work?
June 30, 2022
Teleprompters create the impression of eye contact and free speech
Diagram:
(1) Video camera
(2) Hood
(3) Video monitor
(4) Semi-reflective mirror
(5) Recorded image
(6) Mirrored text
Source (image/text): Wikipedia
The prompter, also called teleprompter (from Latin promptus, "resolute, ready") or "autocue", is a technical aid used above all in television productions as well as talks and speeches to give the audience the impression of eye contact and free speech.
In a TV studio, a monitor is mounted below the camera lens that displays the text mirror-inverted. Via a one-way mirror in front of the lens, the presenter can read from it without taking their eyes off the camera. The quality of the camera image is affected only marginally by this setup. Since part of the light is deflected by the glass, the camera raises the brightness slightly. That way, the impairment is easily compensated.
For talks and speeches, two lightly tinted glass panes are mounted on stands in the right and left area of the speaker's field of vision, with the corresponding monitors or projectors standing on the floor. This way, the speaker can address the whole audience by constantly turning their head, while the center remains an unobstructed view for press cameras.
The displayed text is generated by special software and controlled by the presenter themselves (usually with a foot control) or by an operator. With PPT Mirror, PowerPoint presentations can be used instead of running text. On television, speakers reading from a prompter can be recognized by their eyes constantly moving from right to left. Prompters have been built and used since the 1950s.
Our software tool PPT Mirror lets you mirror a PowerPoint presentation, so it can be used in a teleprompter (see picture)
The big advantage is that you're not reading 1:1 but speaking freely, using the slides of the presentation as orientation. This eliminates the eye movements that come from reading, and your speech becomes more varied in emphasis, pace and pitch. On top of that, the presenter can speak more freely, which comes across as more natural and authentic.
PPT Mirror is ideal for recording talks or training sessions. The tedious "scripting", i.e. writing out the talk word for word, is no longer necessary, which saves additional time.
