The telestrator is a device that allows its operator to draw a freehand sketch over a motion picture image.
The telestrator was invented by physicist Leonard Reiffel, who used it to draw illustrations on a series of science shows he did for public television in the late 1960s. The user interface for early telestrators required the user to draw on a TV screen with a light pen, whereas modern implementations are commonly controlled with a touch screen or tablet PC.
Today telestrators are widely used in broadcasts of all major sports. They have also become a useful tool in televised weather reports.
