That extra stuck layer (the dark one) you are trying to peel off with a knife is the Polarizing layer. BEST way to get it off so as not to damage the screen is to MASTK TAPE over the electronics to protect them then get a load of wet towels and SOAK the black layer of the BACK off the screen then after three hours you can simply peel away the polarizing layer.

Beautiful at 28:30 and 20:56 and 21:12 . 01:16 The PCB 05:44 Removing the back plate. Viewing the white, light reflective back 06:43 LED-back-lit polycarbonate layer with etched dots to let the black light escape the inner total reflection 11:53 Diffusion layer 12:25 Brightness Enhancing Layer recycling the off-axis light 16:21 Some extra diffusion layer? 17:10 The cracked LCD panel 18:25 Driver chips for x-axis and y-axis 19:55 Removal of the frontal polarization layer 20:24 Back polarization layer, pixel close up with macro lens 21:11 Viewing the individual traces to the driver chips 25:24 Pixel and Subpixel viewed with microscope 26:27 Explainaiton and Summarization 28:43 LED backlight efficiency

Just found this video and this channel and while I haven't yet had the time to watch this video in its entirety I couldn't help but smile from just hearing the enthusiasm and joy in your voice as you spoke about this teardown! I can't wait to fully watch this AND a bunch of your other videos!

Dave, the regularity with which you upload your content never ceases to amazes me

It is unreal the amount of complexity that goes into everyday appliances that I take for granted. Awesome teardown. I watch all your videos Dave, keep up all the good work!

Great video Dave, well produced and practically explained, well done! Keep them up, this is how everyone actually learns!

Your teardowns are always amazing, keep it up. Wohoo !

Dave, it was fun to realize, that 5 years after your video, I did this teardown, exactly the same way you did, but only with a broken laptop LED LCD screen (which has the same structure, only with smaller parts). I also lighted up only one part of the LED stripe, and tried to realign the layers to see, how they deal with the light. After my experiments, I tried to lookup some videos, which could explain some things more in detail, and landed up on your video :D It's like watching my discoveries in a replay :D

Thank you so much!! This is video I ve been looking for months!

WOW man.I learned too much from this video. THANK YOU SO MUCH.

Yes please, a follow-up video on the diffusion. Looks super neat!

Hi Dave, I was puzzled by the the types of materials in an edge it TV. Your explanation is very, very good. I needed to see what the order was as some of the sheets can be assembled in the incorrect order. I repaired a TV that could not be watched as it was incorrectly put back together. Some TVs have more or less diffusion materials. I solved it by watching your very simple to understand EEVblog #465 - LED LCD Panel Teardown. I do know that the wrong order explains also the extra diffusion sheets. It is to prevent refraction when two smooth surfaces are placed on top of each other. so the extra diffuser acts as a separator. A pebbled surface prevents this. It is also the reason they are often very this as diffusion is only their second purpose.I assembled an 80" incorrectly and the large patterns an wrong side up/down was not seen until you turned on the TV. Thanks for the video, I have saved it for later sharing. Rinus (Canada) ("Mommy, where is my mommy, they've taken her away!" - Just for you Dave.)

This show literally changed my direction in life. I went from living in the world of software to jumping into the world of hardware. Im now going to be studying electronic engineering rather than computer science. I may still minor in computer science though. You can never have enough knowledge. Please keep doing what your your doing Dave, this is the best show on youtube.

Thanks. I love Hamburg!

7 years late with my comment but I thought that was Brilliant. It was very informative, very well presented and with added humour too. I thoroughly enjoyed it. Thanks for sharing. 😃👌

Another great video Dave!

Yes, that would be interesting with that many diodes in series!

The best, of best, of best ever! Wonderful work!

Thanks Dave! Really useful and interesting video, I really needed those info about diffusion layers etc

Great job! Very interesting . Thank’s for your time.

Nice highlight on the BEF layer.

I'm a fan of the teardowns , always some usefull info in them but this one was particularly usefull for me , thanks :)

Chi-Mei is one of the biggest LCD Panel manufacture, they also produce for LG/Sharp/Samsung ...etc

This is fantastic, great video, thanks!

Thanks for this, have (had?) a happy anniversary

Thank you for the awesome video and your effort.

Outstanding video!

Hi Dave, i really like your videos! You are one of my favorite youtubers. I allready spend hours on watching your videos, but i´m sure it wasn´t a waste of my livetime because i learned a lot:) Greetings from Hamburg in Germany!

best vdo of lcd panel up to the individual pixel level, waiting for so long to know this technology, nowhere mentioned in any of the books!

Really interesting episode! Cheers!

I thought this vid was going to be a real yawner but I was surprised at how interesting that was. I never knew about the amount of effort going into the diffusion and guiding of the light paths.

Great episode, thank you very much!

Take off the top polarizing film of your laptop computer's display, put it into one of these fancy 3d cinema glasses, there you've got your perfect privacy solution for working with the laptop in public: Everyone just sees a white screen, only you with the glasses can see what's going on there :)

Great video full of valuable information.

Thanks for video most thorough I've seen thanks again

Very interesting and very informative video. Thanks Dave.

I need to get me one of those LED strips. This is brilliant!

this optical backlight/filter technology seems rather interesting. i'd love to see more of that!

Wonderful information shared

super interesting stuff! love it!

And Hamburg loves you, Dave:)

In a previous job I once made a pretty kickass UV exposure box from a flatbed scanner, a tanning lamp and the diffusers from a broken LCD.

Love my IPS LCD Bravia!

Very interesting! Thank You!

The most terrifying trace spacing I have ever seen at 21:40

fantastic video thank you !!!

Great video!

Those flex cables going from the driver board to the panel are commonly called TABs. It's short for Tape Automated Bonding, though the process is actually ACF bonding. They are attached with anisotropic conductive film (ACF). The film has microscopic conductive particles suspended in it. Anisotropic refers to an object or substance having physical properties which are different when measured in different directions. When the bonding process occurs, a combination of heat and pressure compresses the tape and this causes the particles to come into contact with each other. The spaces between the traces don't get compressed as much, and thus don't conduct. The anisotropic property of the film is that, after its compressed, it is conductive if measured across the Z axis, but not across X or Y. There is also a driver chip on each tab. When those chips, or the bonds themselves fail, it's known as TAB bond failure. Tab bond failure is a common problem and is the bane of all TV repair techs. It's less common now than it was a few years ago, so they have definitely improved the process, but I still see it regularly. Though it is technically repairable, the cost of the equipment, and the requirement of a class 10 clean room environment puts such a repair out of the hands of most repair shops. A few years ago, a bonding machine was around $45,000 direct from China and the clean room would likely be just as much. Additionally, the tape has a short shelf life and is very expensive. Last I checked, the cost of a China made machine was down to between $5000-8000, I have no clue the quality of those machines, and you still would have the cost of the clean room to consider. Even if I had one, the cost of such a repair would likely be more than most people would be willing to pay. There's probably only a couple facilities in the country which do TAB bond repair, and I doubt they even waste their time doing repairs for the general public. There would certainly be more money to be made doing refurbishing for the various manufacturers (I could be wrong on that though). As for the burnt transistor, it could very well have been the only problem. Sometimes you get lucky and it's just a shorted MLCC, as was the case for me last month when I repaired a 55" Sharp smart TV by replacing a 3 cent capacitor. As for the diffusion sheets under the panel, I'm pretty certain they are made of Mylar, but I don't know much other than that. Here's a good video on ACF bonding. kzfaq.info/get/bejne/mM94ea13rdbVlIE.html

Great Video - Love it

That was very interesting, please do the rest of the stuff with the LEDs and the diffusion film, it would be awesome to see how much of a difference it makes.

Very informative!

Great job again, I love the teardowns, always learn so much about consumer electronics around us. Keep the good work! The panel seems to have quite poor specs, can easily be found by googling M270HGE-L10. Would love to see some high end IPS of VA matrix with greater pixel density. I was thinking the resolution of this one is greater than 1920x1080 resolution but it's not. Can only imagine how small the pixels are on say a 5" Full HD display with 400+ppi.

Fascinating!

Great video as usual =) I've ordered one of the 555 T-Shirts =)

At 23:40, I believe that the pattern in the corner is to balance out the plating area when fabricating the flex. If my memory is correct, plating is a function of current density, and if there are portions of the layer which have significantly more plated areas than other parts, it can cause issues with getting a consistent plating thickness over the whole area of the surface. So the PCB shop may add patterns or ground-plane in unused areas to keep the ratio of plated to un-plated area consistent across the printed circuit.

Very interesting movie, thank you !

hmmm very interesting! I watched your video pondering how hard it would be to convert an LCD screen to work like a vector display.

The led strip with the complete diffusion /reflective white bacgroudn could make a quite nice smooth light source - as a ambient light or placed in a picture frame and perhaps colored plastic in front or some glass collage in front - and its quite low power. Could do for a nice weekend project and nightlight.

Chi Mei Optoelectronics (CMO) IS one of the MAJOR players in the LCD arena, they're a huge monster that manufactures displays for almost everyone else

I've taken apart lots of CCFT LCD monitor panels, and they had 2 directional diffusers - one for X, one for Y.

Awesome! Welcome in from the Dark Side!

@20:44 onward: amazing. Never seen such tiny traces outside of a chip before. Pretty cool.

Thats a really good autopsy on a LED LCD panel!. i am waiting for a damaged big screen LED TV to show up for tear down, I am watching this on a Sharp Aquos 3D LED LCD with its 4 color pixels and I would love to tear into a dead one some day to see how it work!

That backlighting system is quite ingenious. I would have never thought of that. Actually, before I finished watching the rest of the video, I was thinking that the backlighting was the actual thingie producing the display, with the 'dots' somehow turning on/off and reflecting red, green, or blue. Now it seems kind of ridiculous now that I've seen the rest of it. But still, it seems like an intriguing idea. . .

There are two major LCD panel manufacturers in Taiwan, they are CMO and AUO respectively. AUO is owned by BenQ and for CMO, they produce monitors using the brand name "CHIMEI" (or CMV in many years ago)

if you reassemble the panel without the lcd, you get a very nice large diffuse light source that can be used as a light table, novelty lamp, etc. i actually have a reef aquarium that's flourishing under a stripped down 40" sony lcd tv.

DaveCAD, I love it!

Small world. Before I was an EE, I worked at a repair shop fixing VCRs. I didn't get many TVs, the other tech had the monopoly on those. I got the phones and answering machines.

I definitely think you should rig those films up and see the individual effects. Was really hoping for it in this video.

"Dave CAO" should be patented :D Great review, as usually!

The strip has multiple series chains of LEDs on it that look to be individually brought out on the connector, since as Dave pointed out all these LEDs in series would need a massive voltage, like a few 100s of volts.

Love LCDs!

Any chance of an update and more experiments on this Dave?

Excellent macro zoom at 20:50

Hi Dave. The two polarising films are tt a 90 degree angel in relation to each other and thus, normally, no light can pas trough them. But if you place a the LCD panel between those layers you can control if you want the light that goes trough the LCD panel to keep it's polarisation or if you want it to be “garbled” so that it can pass the front polarisation filter. The first I done by passing a voltage trough the crystals witch causes them to face in the same direction! :D

I have some of that funky prism film, seen it dozens of times while tearing apart TVs and monitors, and I've never know till now what it was, how it works or what it's used for. I just assumed it was imbued with some form of dark magic. That LED strip was pretty amazing, too :) That thin strip lights than entire panel? Remarkable! You must try and build some sort of light panel or something :)

That LED strip would work well under a shelf on a bench for general workbench lighting. maybe near a solder station.

thats cool as hell I like keeping the plastic peice that has the etched dots. I use it for project because getting acrilic that thick and size is pretty costly. so when I scrap i use that adn it works great. man I like the have that led strip be great for lighting for some sort of project. great video

It is good to keep the reflectora and diffusers in those monitors, they are great for photography use, eg as a backdrop in a lightbox, they work extremely well in getting that all white background for darker colored items, (makes selecting just the object for a product photo a simple task of using the magic wand tool in photoshop then at most, minor corrections with the refine edge tool.

Take out the LCD panel, leaving everything else. Suspend the top polariser a bit above the rest - Then turn on the LEDs and use it as something similar to a polarimeter. Put a piece of frustration-guaranteed blister pack in - Look at the stress lines which are revealed. Polarised light is COOL!

The inside of a CRT has phosperous lining it. When hit, (at the correct position) they illuminate. That's, what you would see. Along with some x & y plates and magnets used to focus & aim the beam as it scans across the inside of the screen.

Dave, that was WAY cool of a teardown! Thank you. The monitor technology is incredibly interesting. I'd love to see you play around with it some more. What was the voltage fed to that LED strip? Would it be at 40v, or just somewhere up to 40v? I'm not sure how that current box works. BTW, my son (11yrs) wants to see more Sagan vids!

21:50 made me glad for 1080p. At the default 480, it's all a blur. Those are some amazingly close traces.

I just thought of an interesting use. You can use that as a panel to hang paper on to light them up accordingly. In fact I know my work place has several cracked LED screens..

Oh I like to experiment with the BEF layer! I kept my cracked LED screen for one day like this LoL! TY!

you should pull apart a old lcd monitor and run a image through the panel it is quite neat. you can see through it with though is tinted depending on the image. i had thought about making a side too a computer using one and having it run by either a usb video card or something simple too work with for computer stats.

Thanks, but I wasn't questioning his methods. I might have not been clear, so I apologize. I was only offering information about what the datasheet for this LCD panel says is required for the LED backlight.

Thats just incredible. Comparing to ten years ago, the pixel density has probably increased tens of times.. They hve 4K and 5K resolutions at same size, and now to my understanding starting to make or atleast researching 8K ..

Thanks. Yes, I do need a proper professional white balance card I think.

Can you light the whole LED strip? Also how to connect it up and what current and voltage to use. That I could use as a cheap source of light for camping trips and some solar panels to charge the batteries during the day. Tell us more Dave please. :o)

You could put everything but lcd back together and make a really nice white light. Also I bet those large things you thought where test pads where so they could check that the traces didn't get screwed up.

When you was looking for the LED's I was pointing and screaming THEY ARE RIGHT THERE! xD lol

Great teardown. I wonder if you can light up whole LED strip.

@08:28 leds nowadays can have resistos included on the die itself..its a space saving method when you have an entire led strip which is only a few mm wide

WRT to panelization for PnP around 5:00, I've seen PCBs that tabbed and then de-panelized with a router out after PnP and reflow.

Another video on experimenting with the diffusion foils and all that would be really interesting.

Looks like a nice under shelf light. What voltage did it take?

Those are parallel terminator resistors - look at the tracking

23:11 What the heck are those shapes used for on the flat flex? I think I might need to ask on the EEVBlog forum to get an answer to this one, but those look purposefully interesting.

Sweet!