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Every here and there I hear about new LED monitors. I imagined that they were really LED monitors - that their screens were formed of multiple tiny LEDs that lit up in a controlled manner to form an image. Yet turns out they are LED backlit LCD monitors.

What's the difference between this and a trusty Belinea 10 17 51 I've been using for the five years already?

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3 Answers

up vote 11 down vote accepted

For a more in-depth explanation:

You got the concept wrong when you imagined it to be millions of LEDs flashing the different hues of colors to give you a display - all these kind of monitors are made of invariably 2 layers - a front layer of LCD (Liquid Crystal Display or Liquid Crystal Diode) that makes up the dots you see as pixels, along with the display of color.

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This LCD layer is then back-lighted using light tubes at the back, giving it brightness. Formerly, LCD displays use to use CCFL (Cold Cathode Flourescent Lamp) as a light source at the back, but however in recent years there has been a marked shift towards the use of LED (Light Emitting Diode) as a back-light source. The advantages of LEDs are as follows:

  1. Faster Turn On: LEDs can reach maximum brightness faster than CCFLs, in fact almost instantly.
  2. More Neutral Colors: CCFLs are known to give a warm/yellowish tint. LEDs have a more neutral whitepoint.
  3. Brighter: LEDs are brighter generally than CCFLs, thus allowing a display to achieve even higher maximum brightness.
  4. Thinner: The reason LEDs are coming into prominence is that it was driven by the notebook sectors - LED back-lighting can be made thinner than CCFL back-lighting.
  5. Longer-Lasting: Apparently, LEDs are rated for more life than CCFLs. Also the degradation over time is less severe than CCFLs.

Well, these are the primary reasons why LED-based LCDs are considered to be better than CCFLs. They still come with a price premium though.

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LEDs have a lifetime longer than my house... –  RCIX Jun 19 '10 at 10:21
    
LED screens also potentially use less electricity and deeper blacks than CCFL backlit screens. –  paradroid Oct 25 '10 at 7:02
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I believe the blacks on an LED screen are blacker too since portions of the backlight can be turned off when black is needed. A normal LCD, tun the crystal opaque to stop the light coming through. No backlight = better black.

\\Greg

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The backlight uses less energy and generates less heat then fluorescent backlights.

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Emmm... Do you imply that pre-"LED" monitors had fluorescent backlights? That sounds insane. How can a fluorescent lamp be durable enough? –  sharptooth Jun 15 '10 at 6:33
    
O_o Where are you located that has glass which shatters when touched... –  Ignacio Vazquez-Abrams Jun 15 '10 at 6:43
    
I see there is irony in your comment but I'm not a native English speaker and just don't get it. Could you please explain what you mean? –  sharptooth Jun 15 '10 at 6:54
    
I've seen this too. The back light is a fluorescent light at the bottom of the screen and a special kind of plastic is used to evenly distribute the light to the entire screen. You can see this at the bottom of the page here: laptoprepair101.com/laptop/2007/12/09/… –  James T Jun 15 '10 at 7:00
    
@James: I see now. Didn't know they have a special kind of fluorescent lamps suitable for display backlights. –  sharptooth Jun 15 '10 at 7:04
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