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In my perception, the most common color for monochrome computer monitors is green or white/grey, though I have seen orange monitors.

Is this genuinely the case, and if so, is there a reason for it?

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2 Answers 2

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There were a few reasons:

  • Old monitors had very low refresh rates (driven by hardware prices), and green phosphor has the longest afterglow (remains on the screen for the longest time)
  • Green phosphor was the first available for use in monitors (and some sources also say that monitors of this type were physically lighter)
  • It was the brightest type of phosphor
  • Human eye responds to the green color the best, (it's right in the middle of the visible spectrum) (compared to red or blue)

In short, green phosphor allowed to make cheaper monitors

Orange (or Amber which is the proper name) came later under demand from businesses, it was easier on the eyes to read but required faster refresh rate and therefore was more expensive to manufacture.

As a sidenote, many (if not all) monochrome (includes black and white) monitors only use green component (displayed as shades of grey obviously) from the color spectrum when connected to a color signal source, they don't even use other color components. This is easy to observe by hooking up a b/w monitor to VGA output.

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    @Kuba "As a sidenote, many (if not all) black and white monitors only use green component from the color spectrum, they don't even bother mixing other colors in." Then wouldn't it appear green? To get white you have to mix in red and blue. Jun 2, 2016 at 0:17
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    @traal Black and white monitor only displays black and white picture, white means green at 100% brigtness, black means green at 0% brightness. It obviously means huge loss of the actual color information provided by the computer, but for text/office work - no one cares. This is not about additive or subtractive image reproduction using RGB colors on the screen. Jun 2, 2016 at 0:19
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    sidenote could end they don't respond to the other color information signals Jun 2, 2016 at 7:48
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    What exactly do you mean by the bw monitor part? Clearly for the olden times where only those existed, all the signal was bw anyways. In case of TV like PAL, there was an actual monochrome signal available too. Same for most component systems.
    – PlasmaHH
    Jun 2, 2016 at 10:31
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    There was no color signals! It didn't "not respond", it was no such thing. One RCA (baseband video) connector. Not multiplexed channels like a color TV, but basic like the b&w TV.
    – JDługosz
    Jun 2, 2016 at 13:03
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Green was certainly the most common phosphor for a long time, the amber and grey monochrome monitors started to appear in the 1980s, I think.

There are two factors that I think contribute to the choice of colour. One is the stability of the particular phosphor in operation, the other is the related issue of manufacturing quality and absence of contamination, as well as other technical caracteristics of the tubes which maybe offset the cost of the phosphor component.

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    The existance of color tv sets show that different phosphors existed much earlier. But would you really want to use red or blue for a monochrome screen?
    – JDługosz
    Jun 2, 2016 at 13:05
  • @JDługosz Blue would be terrible, since the human eye is not very sensitive to blue. But red doesn't sound so different from orange, and orange was fine. Jun 3, 2016 at 9:31
  • Lots of scopes use blue, and modern LCD monochrome test equipment displays have a blue backlight. Practicality trumps user experience for early tech. Jun 3, 2016 at 9:57
  • Amber monitors are more yellowish than "orange". The ev screens are indeed hard on the eyes and was one reason they were not popular.
    – JDługosz
    Jun 4, 2016 at 2:39

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