Wait a minute, people doing this with projector where using DLP projectors, do you need a OLED smartphone then? Because as far as I know, most screen emit light

Wait a minute, people doing this with projector where using DLP projectors, do you need a OLED smartphone then? Because as far as I know, most screen emit light on black. Or is it reactive to a specific color. I have some doubt about the quality of the printing.