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Science Forum

Science Forum

  1. 20 Feb '11 16:36
    when i put my fingernail up against the computer screen there appears to be liquid behind the plastic. is there really liquid there and if so, why and what kind of liquid ?
  2. 20 Feb '11 17:41
    http://en.wikipedia.org/wiki/Liquid_crystal_display
  3. Standard member sonhouse
    Fast and Curious
    21 Feb '11 04:52
    Originally posted by reinfeld
    when i put my fingernail up against the computer screen there appears to be liquid behind the plastic. is there really liquid there and if so, why and what kind of liquid ?
    You need to update to an LED screen. You have an LCD screen which is in fact a liquid crystal layer, maybe more than one, but it is in fact liquid. Most calculators and digital watches have the same kind of technology, but more crude kinds of liquid crystals.

    LED screens are just millions of light emitting diodes, very small, packed together in a matrix to give full color and high resolution. The other type is the Plasma screen, which is like millions of little neon light bulbs lined up in a matrix.

    It requires rather high voltages applied to the scan lines so uses up more power than either of the other ones, LCD or LED type. Plasma screens have higher contrast and are faster than LCD's but maybe not LED's, so gamers like plasma screens.

    Plasma screens however, have the problem that the front of the screen is rather reflective and if you have a light bulb in back of the screen, you see an annoying reflection on the screen.

    LCD and LED sets have diffused front surfaces that spreads out the light to reduce the effect of reflections so are less annoying in rooms with lights on. In dark rooms, there is not much difference in the three types.

    There is a newer yet technology, OLED, organic Light Emitting Diodes, which will be upcoming, available now but very expensive, will follow the rest of technology, stuff comes out, at first expensive, then price drops dramatically as more folks buy it and more and more are produced.
  4. 21 Feb '11 07:06
    Originally posted by sonhouse
    LCD and LED sets have diffused front surfaces that spreads out the light to reduce the effect of reflections so are less annoying in rooms with lights on. In dark rooms, there is not much difference in the three types.
    My understanding was that LED screens have a much higher contrast ratio. I plan to buy a new screen soon and was considering LED for that reason (despite the higher price tag).

    I currently use CRTs. (I have a 21" and a 19" that I bought second hand).
  5. 21 Feb '11 10:45
    Originally posted by sonhouse
    You need to update to an LED screen. You have an LCD screen which is in fact a liquid crystal layer, maybe more than one, but it is in fact liquid. Most calculators and digital watches have the same kind of technology, but more crude kinds of liquid crystals.

    LED screens are just millions of light emitting diodes, very small, packed together in a matrix ...[text shortened]... expensive, then price drops dramatically as more folks buy it and more and more are produced.
    The neat thing about these OLEDs is that they potentially allow foldable screens.
  6. Standard member mikelom
    Ajarn
    21 Feb '11 11:57
    Originally posted by sonhouse
    There is a newer yet technology, OLED, organic Light Emitting Diodes, which will be upcoming, available now but very expensive, will follow the rest of technology, stuff comes out, at first expensive, then price drops dramatically as more folks buy it and more and more are produced.
    Is the latest affordable within reason, as I have, such as Acer CineCrystal? It says it is both LED/LCD.

    Mine also appears to have a fluid, if I run my nail across the screen, or is this just an illusion?

    -m.