Why Green Mono Monitors?

[Great Hierophant]

Monochrome monitors of the 1980s tended to be green. Whether they were composite or TTL based, the green phosphor monitor always seemed to be the hallmark of the computers of the 70s and 80s. While there were white and amber monitors as well, nothing seemed to be more ubiquitous than the green machine.

Why was this so? Were people tired of boring old white and black displays? Green and black offers nice contrast, but so does black and white. Did the green phosphor last longer?

[apple2fan]

between green/amber/b&w for buyers in the 70s-80s it was about even for all. maybe a few more people DID prefer green than the others but i knew of more people that just used color TVs and bought modulators so they could get the whole color range. (plus monitors tended to be more expensive) Advertisement wise you did see ALOT more green monochrome than anything else. and in movies/TV shows there's a lot of the green. maybe its just soothing to look at. lol

[evildragon]

The color green is easiest on the eyes.

[Druid6900]

The human eye responds to light at 5500nM (greenish yellow) better than at any other wavelength.

At the time the monitors were made, however, it was 5500 Angstroms :)

[apple2fan]

maybe its just soothing to look at
Looks like i was right. LOL

[Yzzerdd]

Indeed, it is easy on the eyes. I also notice that compared to other monochrome (Black & white, mostly) monitors the green-phosphor tends to be lightest in weight. I imagine it was also the cheapest and had the most available range of parts, though. Or maybe the old systems before the true PC used green, and it just stuck?

--Ryan

[Bungo Pony]

I recall someone telling me years ago that the green monitors caused people to go color-blind, which is why they switched over to the amber.

Not sure how much truth there is to that.

[Yzzerdd]

I recall someone telling me years ago that the green monitors caused people to go color-blind, which is why they switched over to the amber.

Not sure how much truth there is to that.

Hmm, well there aren't many color-blind 30+ year olds running around, so I dont think that's quite right. When I first started with the green-screen, it kindof strained my eyes, but I adjusted and now I love it.

--Ryan

[Bill_Loguidice]

I seem to recall reading in some early contemporary magazines when I was little that there was some controversy over the supposed superiority of green monitors over amber, and that in actuality it was a wash. My own preference was always for black and white, but certainly green was ubiquitous. Obviously other factors included actual monitor quality...

[SwedaGuy]

My favorites where the Data General terminals that were blue text on black. Very cool...

[willowmoon93]

Before I ever even got a color monitor, my first monitor was a Zenith amber monitor which I found to be easier on my eyes as opposed to the green monitors.

Blue text on black ... now that probably looked very very cool, I can imagine there would be a good level of contrast.

[evildragon]

I always wanted an amber monitor. :p

Anyone got a amber colored transparency sheet I can put over my model 25? LOL

[vwestlife]

I believe green was simply the first kind of phosphor available way back in the 1800s when cathode ray tubes (CRTs) were first invented, and they just kept using it all along because it was the cheapest. It's the same thing with LEDs: red LEDs were the first kind to be invented, and now even that other colors are available, red LEDs are still the cheapest and most widely used (although green is a close second).

I think the whole thing about green phosphor being "easy on the eyes" is either purely coincidental or just plain junk science made up to justify the continued use of the cheapest phosphor color available. In fact the extreme contrast between the bright green letters and the black background has a rather dazzling effect; with a high enough refresh rate, black text on a paper white background certainly is less agitating to stare at all day.

The most annoying phosphor color I've seen on monochrome CRTs is light blue (cyan), which I've seen on Amdek mono composite monitors (also available in green and amber phosphor) and some old ATMs (now probably long out of service).

My favorite was an IBM paper white mono VGA monitor, model 8503 I believe. Unlike the classic Macintosh monitor which has a bit of a blue/cyan tint, IBM's white phosphor has a slight off-white "eggshell" tint, which was very pleasant to my eyes, especially with VGA's relatively high resolution.

Outside of CRTs, the worst of all time has to be the reddish-orange gas plasma displays commonly used on "lunchbox"-type portable computers in the late '80s. Staring at one of those makes a Tandy VGM-200 (VGA color with 0.52 mm dot pitch) look beautiful in comparison!

[vwestlife]

Advertisement wise you did see ALOT more green monochrome than anything else. and in movies/TV shows there's a lot of the green. maybe its just soothing to look at. lol
That could simply be because it shows up on the camera better. (That's why whenever someone writes something on a piece of paper and shows it on camera, the paper is inevitably light blue -- because it shows up better than white paper. Match Game... Pictionary... even David Letterman's cue cards... the paper is always light blue!)

[nige the hippy]

In the earlier days (pre-about 1983) I think that the reason green was predominant was that the green phosphors had a longer persistence (i.e. they glowed for longer after being energised by the electron beam) meaning text and other non-moving displays flickered less.

I remember when amber started to come in & all the talk was that it reduced eye strain (although personally I preferred green), it also had the advantage that it looked better with the then fashionable brown & cream cases (& left over late 70s decor!)

I suppose that long-persistence phosphors went out and were replaced by faster scan-rates as gaming came in, there's nothing more annoying than great blurry trails of "videoplasm" following you around the screen.

[Dwight Elvey]

Before I ever even got a color monitor, my first monitor was a Zenith amber monitor which I found to be easier on my eyes as opposed to the green monitors.

Blue text on black ... now that probably looked very very cool, I can imagine there would be a good level of contrast.

Hi
Blue is the worst color to focus on. Green is best, next is red.
As for color blind, you have to be born color blind, you won't
have more than temporary effects from single colors.
Dwight

[evildragon]

just curious. I saw a monochrome CRT at the thrift store, which had a switch that said "GREEN/AMBER".

how does that work?

[vwestlife]

just curious. I saw a monochrome CRT at the thrift store, which had a switch that said "GREEN/AMBER".

how does that work?
That's not a monochrome CRT. It's a color monitor which can emulate a monochrome display by switching the entire screen display to green, amber, and/or white. This switch was common on early multisync color monitors which could display MDA/Hercules video.

When in doubt, look closely at the CRT (a maginying glass helps). Color CRTs have tiny bunches of red, green, and blue dots next to each other. Monochrome CRTs do not have these visible pixels, as the entire screen is just painted with single-color phosphor.

[billdeg]

The switch from green to amber was driven by business systems, in that the demand for amber came from business customers. I seem to remember it that way.

[CP/M User]

The original Amstrad CPC machines (from 1984/5) either came with Colour Monitors or Green Screen monitors - that was it. The push for Green Screens in that situation was based on if you were using Serious applications such as Word Processing, Spreadsheet, Database, etc. None of the CPC machines had the option of an Amber monitor and of the Amber monitors I've seen - I'd much rather have a Green Screen than Amber Screen. The Amstrad PCWs I believe only came with Green Screens as Standard.

Of the one demo I had for a Green Screen which I've mentioned numerous times before (which for those new here or missed those posts before hand is an Interlace Demo) which, worked at producing a High-Resolution screen by flashing characters onto it, was ideal on a green screen because flashing on a green screen isn't so prominent when compared to a Colour monitor and perhaps Amber has the same problem?

[vwestlife]

Of the one demo I had for a Green Screen which I've mentioned numerous times before (which for those new here or missed those posts before hand is an Interlace Demo) which, worked at producing a High-Resolution screen by flashing characters onto it, was ideal on a green screen because flashing on a green screen isn't so prominent when compared to a Colour monitor and perhaps Amber has the same problem?
That's likely because the monochrome monitor had a longer-persistence phosphor, as they commonly use to reduce flicker. For example, the IBM MDA standard has only a 50 Hz refresh rate (same as used for TV in Europe) and on a color monitor that accepts MDA signals, the flickering is very visible, but on IBM's original green-screen monitor, the phosphor takes so long to fade out that you don't see the flickering at all.

The only color monitors I've heard of with long-persistence phosphor were a few from Commodore, designed to make the interlaced high-resolution modes on the Amiga (30 or 25 Hz effective refresh rate) look acceptable.

[CP/M User]

vwestlife wrote:

That's likely because the monochrome monitor had a longer-persistence phosphor, as they commonly use to reduce flicker. For example, the IBM MDA standard has only a 50 Hz refresh rate (same as used for TV in Europe) and on a color monitor that accepts MDA signals, the flickering is very visible, but on IBM's original green-screen monitor, the phosphor takes so long to fade out that you don't see the flickering at all.

Yes, that's the explation I was looking for, so do you know if Amber based monitors give off same effect or do they generally flicker a lot more?

[vwestlife]

Yes, that's the explation I was looking for, so do you know if Amber based monitors give off same effect or do they generally flicker a lot more?
It really depends on the particular monitor, rather than what color the phosphor is. Generally, the lower the refresh rate the monitor was designed to accept, the longer the phosphor persistence will be.

[Micom 2000]

I always wanted an amber monitor. :p

Anyone got a amber colored transparency sheet I can put over my model 25? LOL

If I looked hard, among my monitors I likely have an amber one looking for a home. They weren't uncommon. The ones I still have an affinity for are the Red plasma screens.

Lawrence

[Floppies_only]

I recall someone telling me years ago that the green monitors caused people to go color-blind, which is why they switched over to the amber.

Not sure how much truth there is to that.

I believe that it's not true.
If you believe in evolution, you believe that man evolved in an environment full of green plants. But he needed color vision to find fruit, which signals it's presence with bright colors that also indicat the presence of cancer fighting phyto-nutrients.

Green was the original color that eyes could see. Squirrels are still limited to only seeing that color. A lawn of grass looks white to them. I suspect that green, being the original color that eyes could detect, is more easily seen by human eyes. The other colors might require more brightness to be detected.

So, the engineers who designed green screens (starting with radar screens) were attempting to save power. I'm sure that my IBM 5151 monitors use a lot less power than a newer SVGA monitor.

Sean

[im_an_alien]

I have an amber monitor for my XT, and I like it a lot. I don't have a green monitor (except in my compaq portable, but considering the enter key is broken on that one, I don't exactly use it much), but I think I'd prefer amber.

[Floppies_only]

I have an amber monitor for my XT, and I like it a lot. I don't have a green monitor (except in my compaq portable, but considering the enter key is broken on that one, I don't exactly use it much), but I think I'd prefer amber.

I've heard from a person who didn't like bright light that preferred his amber monitor.

Those Compaq portables are bad about their motherboards quitting. Maybe you can get somebody with a broken one to take the keyboard off and send it to you. I don't remember them as being too hard to work on.

Sean