Taking Apart An LED TV

This one hurts to write. We bought a 47″ LG LED Smart TV last January. It was a nice TV, bright picture, and it would play streaming video. Very cool. I had it on it’s stand in the den, and then a couple months ago one of the cats tried to leap on top of it, found the couple inches thickness too narrow to stand on, and managed to push the TV off for an almost-four-foot fall to the floor. The think was sporting multiple impact spiderwebbing on the display, and is useless. It would cost more than a new (larger!) TV to fix it, so I reluctantly took it apart. It was remarkably simple in terms of the number of parts.

Since I was wanting to take a look at the processing end of the TV first, that’s what I went for. It’s worth noting that the entire disassembly was done with a #2 Phillips screwdriver.

There are a total of seven PWBs in the TV. Four of them were small; two drove the LED array, and the other two, I think, drove the status LEDs in the bezel and handled the IR remote. Here are the other three.

The PWB to the left is, I think, a driver for the four speakers in the TV. The center is a CPU board. It as all the inputs and outputs for video and sound. There was no obvious GPU, but I’m going to look up some of the part numbers, but I suspect that all the processing is done via custom IC. The board to the right is the power board.

The business end of the TV is here. It is built of a set of layers that are fixed to a fairly rigid metal frame.

The three PWBs were mounted to the back of the frame. The frame has an array of white LEDs inset (there is a closeup below), which are the backlight for the TV. The white LEDs are on the other side of the frame also.

The first layer is basically a white piece of plastic. I imagine it is essentially a reflecting surface to make sure all the white light is headed towards the viewer.

Next is a translucent panel that has grooves machined into one side. I looked at it using a magnifying glass, and it looks like the grooves are at a 45deg angle to the vertical. This panel would reflect the white light from the LEDs out towards the viewer.

On top of the translucent panel are a pair of translucent panels that are not grooved. I speculate that these two are diffusers to soften the LED light from the grooves to make it more even.

Finally, the last panel is the LED array, known as the “glass”. This part is seriously cracked.

There were other mechanical parts that I didn’t pay a lot of attention to, as they are very straightforward, such as the stand, trim pieces, the bezel, and the like.

This is a closeup of the backlight LEDs.

So ends our nice TV. We’ve been making do with a 19″ panel until we buy a new one. In case you are wondering, yes, the cat is still alive. My lesson learned here is to mount the TV to the bookshelves in back of it next time. Oh well.

Advertisements

2 Responses to “Taking Apart An LED TV”

  1. Jen Says:

    Interesting. Thanks. The high-$ Apple 27″ displays aren’t too different. An old RadTech here, and an LG Flatiron we have obviously has a need for a new 3.5mm headphone socket, or dab of solder. Trouble is the new designs are elegant in the extreme, and obvious put together like a plastic model, just popping tabs into recepticles. So. How to break into a plastic flatpack?

    Any hints on how to detect where the tab/hole joiners might be?(Without dropping it 4′ onto the floor, ideally )

  2. Food Crisis No Problem Says:

    May I just say what a relief to uncover somebody that actually understands what they are
    talking about on the web. You certainly know how to bring an issue to light
    and make it important. More people have to look at this and understand this side of the story.
    It’s surprising you aren’t more popular since you
    certainly have the gift.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: