Teardown of a Laptop monitor (questions inside)

Discussion in 'General Electronics Chat' started by Cretin, Jul 3, 2013.

  1. Cretin

    Thread Starter Member

    Dec 13, 2012
    So long story short my old laptop screen suffered some water damage. I read up a bit on the issue and on most forums the general consensus was to toss it and buy a replacement.

    but...that's where the fun begins :) I took it all apart today, and with the help of this video I was really amazed by the elegance of how LED screens are engineered.

    As always, a few questions with some pictures of course!

    1: This image is of a thin sheet that was sandwiched in the middle of the laptop screen between other sheets. I'm not quite sure what it is exactly or what it is made of but what I can tell you is that when I hold it up it and look through it I see a hazy rainbow of colours, similar to what you'd see when you look through 3D glasses in old kids magazines.


    2: The video linked above says that each row of pixels in the laptop are activated by a single transistor. Are the circles in the image below all transistors?


    3: Is this where the laptop would be connected to the motherboard/GPU?


    4: What is this adhesive for?


    5: Should I keep any of this stuff around? Could I find some use for it in other applications?
  2. Markd77

    Senior Member

    Sep 7, 2009
    1) Probably the primary colour pixel mask. If you look at it through a magnifying glass and you see tiny red green and blue areas, that's what it is. Keep it because it looks nice. You should find two other sheets and if you look through them both and rotate one, it should block or allow light to pass. They are the polarisers.
    2) Nope, one of the chips will contain all the transistors, the ones labelled C in your oval are capacitors, R are resistors.
    3) Could be.
    4) Probably thermal compound to attach to a heatsink
    5) Probably not (apart from the stuff that looks nice), it's mostly custom chips that don't have any other use, or components that cost fractions of a penny anyway.
    Cretin likes this.
  3. Cretin

    Thread Starter Member

    Dec 13, 2012
    Thanks for the reply Markd77, I'll keep the primary colour pixel mask as a sentiment.

    Also thank you for clarifying the components for me....seems so obvious now that I look at it again, but I guess that's why it's good to ask :)
  4. studiot

    AAC Fanatic!

    Nov 9, 2007
    I agree with Mark on 1 - 4 but for 5, look on Ebay type in your laptop model and 'spares'. You would be suprised how much people are paying for parts.
    The screen hinges often fetch good money.

    Edit 'one of the chips will contain all of the transistors'

    Not really there are many discrete transistors on a laptop board. They can be identified by three connections rather than 2, but beware of other three terminal devices such as regulators.
  5. ian field

    AAC Fanatic!

    Oct 27, 2012
    Always a good source of multilayer ceramic chip capacitors - upto 22 or 47uF in a tiny package, handy for taking the edge off ripple current in electrolytics that run hot in SMPSUs.