One of my cameras makes B/W screens look very bluish. I think some of it has to do with shooting under comparatively yellowish indoor lights. The camera does some kind of color average (is that the right term?) with the room as a whole and gets the colors right for the cabinet, drapes, etc, but the screen comes out too blue. It's so blue that, for photos I want to use on my website, I sometimes cut out the screen portion and convert that to greyscale so that it doesn't look ridiculous. This effect is true of all my B/W sets, with various CRTs; they all display shades of grey to my eyes but the camera turns them weirdly blue.
Try turning out
all of the room lights and taking a photo of only the screen. Then turn on the room lights, photograph again, and compare blueness of the screen in both shots.
I'm not saying that phosphors don't have different colors, only that I've seen this very obvious effect when shooting photos under warm indoor lights.
Phil "not a serious photographer" Nelson
Phil's Old Radios
http://antiqueradio.org/index.html