After watching the video again I realized the screen has some kind of digitizer behind it. That was highly unusual for touch screens of the era.
Most touch screens from the 80s were not actually sensing touch; instead they had light beams and sensors in a grid around the screen. Your finger would interrupt the light and the sensors at the x and y axis would determine your finger's placement over the screen.
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After watching the video again I realized the screen has some kind of digitizer behind it. That was highly unusual for touch screens of the era.
Most touch screens from the 80s were not actually sensing touch; instead they had light beams and sensors in a grid around the screen. Your finger would interrupt the light and the sensors at the x and y axis would determine your finger's placement over the screen.