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I got this new laptop I bought few days back and I was taking good care of it when yesterday a friend touched the monitor, I don't know how hard he touched but that sudden glow happened that you get when you touch an LCD screed, but nothing has happened and I don't see any dead pixels, will anything bad happen to my monitor because of what happened?

Thanks

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@50-3 well my laptop is a pretty solid one so i think the build quality is pretty good, i'm just ocd i guess :) thanks :) –  zpaer Sep 22 '13 at 9:45
    
@50-3 consider adding your comment as an answer :) seems to me pretty accurate. –  Lorenzo Von Matterhorn Sep 22 '13 at 11:06
    
@Lorenzo done comment removed –  50-3 Sep 22 '13 at 11:12
    
If it looks fine now it should be fine. Any damage would probably be immediately visible. –  Daniel R Hicks Sep 22 '13 at 12:18
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2 Answers

Coming from corporate IT support I've seen users knock over monitors they poked them so hard and never noticed any long term damage. It will depend heavily upon the build quality of your display but unlikely to be anything long term.


Originally comment, moved to answer

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I was going to write a more complex answer explaining about how touching an LCD could disrupt the liquid crystals between the film layers but that unless it was a long term thing it wasn't of much concern. Check this page for more info on LCD's. –  Doktoro Reichard Sep 22 '13 at 11:15
    
@DoktoroReichard well it's actually an LED display so does it make any difference if it's LED? –  zpaer Sep 22 '13 at 11:28
    
All the difference. They are different technologies. Using LED's (Light Emitting Diodes) you don't have the problems of the LCD's (Liquid Crystal Displays). –  Doktoro Reichard Sep 22 '13 at 11:29
    
@Dokotoro do it you will get my upvote and I was hoping someone would that's Why my answer was originally a comment to not put people off posting good answers but someone asked me to put it as an answer –  50-3 Sep 22 '13 at 11:30
    
@DoktoroReichard so it means that touching must not have created any damage that would have gotten if it's LCD? –  zpaer Sep 22 '13 at 11:31
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An LCD display is composed of a technology based on the properties of liquid crystals and, more importantly, depends on the way the liquid crystals are embedded on the matrix.

The following is a schematic of a LCD cell I got from HowStuffWorks

LCD Schematic

LCD's work by changing the angle at which light passes through them:

If we apply an electric charge to liquid crystal molecules, they untwist. When they straighten out, they change the angle of the light passing through them so that it no longer matches the angle of the top polarizing filter. Consequently, no light can pass through that area of the LCD, which makes that area darker than the surrounding areas.

If the LCD matrix is disrupted, light may not pass as it should. Light may be completely blocked, or may be completely passed. This creates an effect know collectively as a dead pixel (although, as Wikipedia points out, there is a technical difference between dead and stuck).

This happens if you place too much pressure at one point of the display, or by natural causes (due to heat, temperature, humidity, or sagging occurring at the surface level). It also explains the rainbow-colored effect that happens while you press the display: the crystals are being moved (microscopically) from their original positions and light passes at a new angle, that then diffracts.

Comprehensively it is hard to take a screenshot of the problem (as the display signal is working right). I managed to get this image from Google, the dead/stuck pixels are the light dots on the display.

Dead pixel

To fix this, a good way is to simply (and gently) tap the area surrounding the dead pixels with a blunt object (a stylus or a pen cap). That will force the crystals inside to rearrange to their original positions.

However, crystal display are quite resilient, as @50-3 stated. Mainly because the display is somewhat rigid due to the amount of circuitry and connecting films.


As you can see in the diagram, there exists a light source behind the LCD film. That usually was a set of florescent bulbs (in older models) and in some badly-made models some light could be seen from the seams that hold the film to the display.

More recent developments in LED technology have made it possible to use that as back-lighting.

LED (Light Emitting Diode) are simply a set of two doped silicon pieces that, when electricity runs through them, create an effect similar to a voltaic arch. Quoting from HowStuffWorks:

They are illuminated solely by the movement of electrons in a semiconductor material, and they last just as long as a standard transistor. The lifespan of an LED surpasses the short life of an incandescent bulb by thousands of hours. Tiny LEDs are already replacing the tubes that light up LCD HDTVs to make dramatically thinner televisions.

This is a LED (retrieving the schematic from Wikipedia):

LED picture LED schematic

I assume any one has at least seen one, because the are everywhere. Now, think that it can be reduced to about a fraction of their size, placed millions of them on a board, and give them colors.

There you have an LED display. LED displays have two main differences in regards to LCD: 1. They are more durable (i.e. no moving (or flowing) parts). 2. They don't require back-lighting (LED's provide heir own light).

This being said, since LED's are just a piece of silicon, they are as durable as the silicon board that holds them all together. And they can take as much abuse as any board can take. So, they are impervious to nudging and impacts, to some extent.

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I was under the impression most "LED" TVs had LED backlights, rather than being OLEDs - which are actual tiny LEDs printed on a board. I wouldn't consider a LED being any more physically robust than an LCD other than the lack of inverter, and that LEDs don't gradually burn out like CCFLs, they just drop dead eventually –  Journeyman Geek Sep 22 '13 at 12:09
    
My knowledge was the same, have you got any resources to back it up. Also I would say being rigid as beneficial to the durability of a LCD display as it would be more likely snap if it was rigid –  50-3 Sep 22 '13 at 12:41
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