Why? What’s so hard about making micro-LED TVs? And if it’s not micro-LED, then what is the next big thing in displays, and into what tech should we put our hopes and dreams?

I am going to try to explain everything in easy-to-understand terms, and my hope is that your expectations will be fairly managed and we can all avoid further disappointment next year.

What are micro-LEDs?

First, here’s a quick primer on micro-LED.

LEDs work in today’s LED, mini-LED, and QLED TVs — which are actually LCD TVs — as a backlight. The pixels are in the LCD layer and they use color filters — sometimes also quantum dots — to make the picture you see. The LEDs or mini-LEDs are basically flashlights in the back of the display creating the light. They don’t make the color or the picture, and they are not pixels.

A micro-LED display is different because the minuscule light-emitting diodes (micro-LEDs) are the pixels. Micro-LED displays have more in common with OLED TVs in this way. You apply voltage to these micro-LEDs, which are broken down into red, green, and blue subpixels that, when combined, can make any color you want. There is no color filter or LCD layer — just tiny lights combined to make a picture. They can get much brighter than the compounds used in OLED TVs. It’s the best of all worlds: perfect black levels, infinite contrast, and extreme brightness along with the hugest color volume possible. That’s why micro-LEDs look so amazing.

What is so hard, then, about making a micro-LED display? There are several challenges, but the primary challenge is pixel pitch.

Pixel pitch refers to the distance between the centers of two adjacent pixels. For context, the pixel pitch on the 4K version of Samsung’s 146-inch “The Wall” micro-LED display is 0.84 millimeters — that’s 0.84 millimeters between the centers of each pixel to get 4K resolution that doesn’t appear to be pixelated or blocky from normal viewing distances in typical homes.

On the 89-inch 4K version of Samsung’s micro-LED display, the pixel pitch is about 0.8 millimeters — a little tighter. The pixel pitch of a 75-inch micro-LED display would need to be about 0.43 millimeters. That’s about half of what we see in Samsung’s 146-inch “The Wall.”

That’s a massive challenge. The robots tasked with placing the micro-LEDs on a substrate have to be incredibly precise (those are some massively expensive robots). As precise as they are, the yield of acceptable micro-LED displays with that kind of pixel pitch is relatively low because if there are any errors — if anything is out of alignment even just a tiny bit at that tiny scale — it will be pretty visible. Larger micro-LED displays are much more forgiving, relatively speaking. We tend to view them from farther away. That’s why we see them used successfully as huge display signs or, in Sony’s case, as realistic-looking backgrounds for film sets.

Not only is pixel pitch a huge challenge to pull off from a printing perspective, micro-LEDs also generate a lot of heat. The tighter you have to cluster these micro-LED pixels, the more heat management needs to be implemented — and that has also been extremely challenging.

This is perhaps why most of the micro-LED prototype displays we’ve seen have been modular. I don’t know if it is slightly less challenging to make a smaller module, but I do know that it’s way easier and way less expensive to toss out a bad small module than it is to make a big one and then have to toss the whole thing out if there’s a defect. Heat management is also a little less challenging when you do it at a smaller, modular level.

In short, making micro-LED displays is extremely difficult, extremely expensive, and has low yield. That is just bad business. If you can only make a few of something that will be massively expensive, you won’t likely sell many and you’re probably going to lose money or, at best, break even.

But, you might ask: Wasn’t Apple going to make micro-LED displays for Apple watches? They tried, and then canceled those plans because it was too expensive and didn’t add sufficient value.

I’m not suggesting that a true RGB micro-LED TV will never be in your living room, but I feel fairly confident that it won’t be happening any time soon. I’m OK being proven wrong, though. For now, I’d rather keep my expectations low to avoid disappointment, and if it does come to fruition soon, I’ll be elated.

Quantum dots to the rescue?

There may be hope for micro-LED in the near future. It might be possible to ease the pixel pitch problem a little, and therefore lower costs and yields, with a technology that’s become almost ubiquitous in TVs over the past 11 years: quantum dots.

Quantum dots — “Q” in QLED or the “QD” in QD-OLED — are tiny nanoparticles that glow a certain color when light of a certain wavelength is shone on them.

However, it could be possible to ditch the red, green, and blue micro-LED subpixels and instead take a QD-OLED-like approach to micro-LED by using one specific color of micro-LED and getting the rest of the colors from quantum dots. When micro-LED does land in our living rooms, I feel pretty confident this is how it will work. How close are we? Honestly, I don’t know. I think we’re several years out, but again, I’d love to be proven wrong.

Still, I think QD-micro-LED is the way to go.

If not micro-LED, then what? What could be the next-level display tech that revolutionizes TVs? I think it will be quantum dots to the rescue. Except in this scenario, the quantum dots won’t simply glow when light is shone on them. They will make their own light just like micro-LEDs and OLEDs do. I’m talking about electroluminescent quantum dots, which in inner TV-nerd circles we’ve been calling QDEL.

Sharp Display Corp is actively working on QDEL technology. During CES 2024 it was very much in its early stages, but Sharp has made progress — how much, I don’t know. (I also don’t know if Sharp is going to show it to me at CES 2025. I have asked, though, and I am hopeful.)

According to Sharp, making a QDEL panel is not that challenging. In fact, existing production methods can be used, and it doesn’t have to be done in a vacuum — literally in a vacuum environment. The cost of production won’t be all that high, and lower than OLED, according to what I’ve been told. In that way, QDEL sounds extremely viable.

The trick is going to be ramping up the brightness. As I understand it, the challenge is making a more efficient — or brighter — blue electroluminescent quantum dot. The red and green quantum dots are pretty well-dialed, but the blue needs to catch up in order for a QDEL display to get sufficiently bright. I understand some progress has been made, but I don’t know to what degree. QDEL is the display tech I’m most excited to learn more about at CES this year.

You might also ask: What about PHOLED — or phosphorescent OLED technology? What is it and how does it fit into this discussion?

Phosphorescent OLEDs are more efficient than standard OLEDs. You can get more brightness with less electricity. Again, it’s that blue color holding things back. Blue PHOLEDs are less efficient than red and green PHOLED compounds, which has been holding back PHOLED displays from getting to that next-level brightness we want. PHOLED does hold the promise of reducing burn-in risk and reduces energy consumption — both factors that make pursuing PHOLED desirable.

For me, though, PHOLED is more evolution than revolution. So, I’m still more excited by the idea of a QDEL TV and quantum dot micro-LED TV.

In the end, we’re going to have to wait to see what happens at CES 2025. I have my doubts that micro-LED is the undisputed king of future TV tech — at least in the short term. I would not expect inexpensive, “normal-sized” micro-LED TVs to appear on store shelves in 2025.

I think we’ll see promising progress at CES, but in 2025, I think most of the TVs on store shelves are still going to be mini-LED LCD TVs and OLED TVs, much like the TVs we got in 2024. However, I expect they will be a lot more expensive in 2025 than in 2024.