• Sign in to Neowin Faster!

    Create an account on Neowin to contribute and support the site.

Sign in to follow this  

Why were LCDs commonly green back lit when grayscale?

Recommended Posts

neufuse    3,550

Don't know why this just popped in my head but why did we have this obsession with grayscale and monochrome screens being back-lit with green light back in the 90's? I know white LED's were not as common back then but it seemed like there was almost a reason to do this color? Just curiours

Share this post


Link to post
Share on other sites
+Zag L.    675

I dont ever remember an LCD monitor being backlit in green. Can you share a link showing one?

Share this post


Link to post
Share on other sites
Ready2018    41
1 minute ago, Zag L. said:

I dont ever remember an LCD monitor being backlit in green. Can you share a link showing one?

Back in the day when laptops were first introduced (not that they were anything like the small laptops you get today) they had either green or orange screens

Share this post


Link to post
Share on other sites
Jim K    12,612

Talking about old monochromatic monitors? Low refresh rate which needed a cheap/long-after-glow phosphor to reduce flickering ... green it was. At least that is my understanding of it.

Share this post


Link to post
Share on other sites
Brandon H    2,693

Green was probably one of the easier colors to replicate too on the basic RGB pallet. was more pleasing to the eye than Red, and blue I could see being too soft a color

Share this post


Link to post
Share on other sites
DonC    577

Here's an entry on the retro computing Stack Exchange site about green screens:

 

Quote

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.

 

 

  • Like 1

Share this post


Link to post
Share on other sites
DonC    577

Wait wait..

 

Are you talking about green screens or the green backgrounds on things like the Nintendo Gameboy?

Share this post


Link to post
Share on other sites
Xenon    4,923

Because they were cool.........

  • Haha 1

Share this post


Link to post
Share on other sites
neufuse    3,550
Posted (edited)
1 hour ago, Jim K said:

Talking about old monochromatic monitors? Low refresh rate which needed a cheap/long-after-glow phosphor to reduce flickering ... green it was. At least that is my understanding of it.

no, I'm talking about LCD... an example is the Apple Netwon it had a green backlite.. a lot of windows ce products when they were new and monochromatic / grayscale used green the later switched to a light blue color... gameboy actually had a green refection layer on it (no backlight though)

1 hour ago, Ready2018 said:

Back in the day when laptops were first introduced (not that they were anything like the small laptops you get today) they had either green or orange screens

oh gawd I forgot about the orange back lights

Share this post


Link to post
Share on other sites
neufuse    3,550
1 hour ago, DonC said:

Wait wait..

 

Are you talking about green screens or the green backgrounds on things like the Nintendo Gameboy?

background and back lights at the time seemed to primary be reflective green (gameboy) or back lit with green led's (when they didn't use CFL tubes)

Share this post


Link to post
Share on other sites
goretsky    1,004

Hello,

 

It is my understanding that the reason old monochrome (1-bit) LCD screens had a green or bluish-green background is because that was the natural color of the liquid crystal material used, at least at human-comfortable temperature ranges.

 

Regards,

 

Aryeh Goretsky

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.