Gibson has said that he was imagining a TV from when he was growing up. Quote:

"I actually composed that first image with black and white video static of my childhood in mind, sodium silvery and almost painful, […] the texture and color of a signal free channel on a wooden cabinet motorola with fabric covered speakers.

So like this:

https://www.youtube.com/watch?v=S_7yUDne8fg&t=260s

eidetic - “pertaining to the faculty of projecting images,” 1924, from German eidetisch, coined by German psychologist Erich Jaensch [n.b. born 1883, died 1940], from Greek eidetikos “pertaining to images,” also “pertaining to knowledge,” from eidesis “knowledge,” from eidos “form, shape”