An office machine that photocopies in color, such as 3M's Color-in-Color (1968) and the Xerox 6500 (1973). Sonia Landy Sheridan and her Generative Systems program in Chicago used it as an art medium.
And we had a copy machine called the 3M Color-in-Color copier with a backlight setting. I was working on an Apple computer, which, of course, I believe, was eight colors, and the pixels were boxes.
Joan Truckenbrod, The 1970s Artist-Programmer: Truckenbrod, Dehlinger