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Kay Red Green and Blue for Technicolor are used for screens worldwide. More on Technicolor at: http://www.digital-intermediate.co.uk/examples/3strip/technicolor.htm#:~:text=Technicolor%20is%20a%20colour%20film,its%20saturated%20levels%20of%20colour.&text=The%20process%20involved%20capturing%20the,individual%20black%20and%20white%20negatives. This transfered over into the Cathrode Ray Tubes of the 70s & 80s and beyond. https://www.newworldencyclopedia.org/entry/Cathode_ray_tube The red, green,blue became a standard in almost all screens globally and has remained.
See this: https://en.wikipedia.org/wiki/RGB_color_model#:~:text=Additive%20colors,-Additive%20color%20mixing&text=To%20form%20a%20color%20with,reflection%20from%20a%20white%20screen).