Tandem OLED! Awesome, right? Wait … hold the phone. Tandem OLED? What in the what?
Did Apple geniuses just smash together two OLED panels and, et voilà, a brand new, unprecedentedly awesome display is born, exclusive to the new iPad Pro? Well, not exactly. There’s more to it than that, and in the end, it’s great news for all of us.
Digging into the world of Tandem OLED
I first heard about Tandem OLED from fellow journalist and friend Jaron Schneider over at PetaPixel. He texted me, “Please do a video that explains how WD-OLED and Tandem OLED differ and what makes each special.”
To which I replied: “Uhhhhh … Tandem WHAT?”
I’m a TV expert – which doesn’t necessarily mean I’m a display expert, but maybe a display expert-adjacent? I spend a lot of time on the bleeding edge of display technology, especially anything involving OLED. So, imagine my surprise when Jaron – and then a host of others – started texting me questions about Apple’s new Tandem OLED tech on the 2024 iPad Pro.
Not knowing anything about it, I immediately began looking into it, starting with Apple’s own description. As Apple explains: “We developed a state-of-the-art display that uses two OLED panels and combines the light from both to deliver phenomenal full-screen brightness. No other device of its kind delivers this level of display quality.”
Apple then goes on to explain all the benefits inherent to OLED display tech and announces it as “Ultra Retina XDR.”
So, brass tacks: What makes the promised performance of this screen so remarkable is its high brightness – 1,000 nits full-screen and 1,600 nits peak brightness for HDR highlights. That is awesome, indeed. But is it the best OLED display you can get in a consumer device? And how in the world does using two OLED panels work? Is it an OLED sandwich of some sort? And did Apple really invent this?
To better understand Tandem OLED technology, let’s start at its beginning – which did not take place in an Apple laboratory.
Apple didn’t invent this
I found a white paper submitted in 2009 as part of the Society for Information Display (SID) Display Week Symposium, an inside industry trade show for the latest in display tech. Tandem OLED, or at least the concept of it, was developed 15 years ago — about two years before LG introduced the first consumer OLED TV.
Since then, numerous developments have been made to make it more efficient, and several more white papers have been issued talking about its advancement into a fully baked technology.
So, if the tech has been around for so long, why haven’t we seen Tandem OLED in a device before? Let’s come back to that. First, let’s talk about the two most popular types of OLED panels used in devices today.
One is called W-OLED, or WRGB OLED – also referred to as white OLED. This panel uses organic compounds to make red, green, and blue pixels that produce their own light – no backlight needed. Then, a white OLED subpixel is added to boost brightness. LG Display has pioneered this technology, and for years, it was the only kind of OLED panel you’d find in TVs and PC monitors.
A couple of years ago, Samsung Display came out with a new type of OLED panel called QD-OLED. This uses just one blue OLED pixel to create light and then adds red and green quantum dots, which are tiny nanoparticles that glow when you shine light on them. QD-OLED panels make more pure red, green, and blue light than W-OLED panels, so they tend to have better color brightness and color purity.
Apple described the advantages of OLED tech as perfect black levels, amazing contrast, incredible pixel response time, and rich, accurate color. Year after year, OLED TVs are named as having the best picture quality.
Why Tandem OLED is such a big deal
If OLED is so awesome, why isn’t it used in everything? It’s because OLED’s Achilles’ heel is that it’s an organic material, so it wears out faster the harder — or brighter — you drive it. That being the case, to protect OLED panels from burning out too soon — or burning in — TV manufacturers have to cap how hard they drive them.
Also, the bigger an OLED display is, the more power it gobbles up. In a portable device like a tablet, that means it’s going to eat up the battery pretty quickly. So, while an OLED display might work just fine in a phone, it’s going to be a bit too power hungry to work in a larger battery-powered device like an iPad.
Enter Tandem OLED. It is a W-RGB OLED panel type, but it uses two light-emitting layers, each driven with a relatively modest amount of power, so we’re not going to wear those OLED pixels out. Since there are two light-emitting layers, that also makes Tandem OLED capable of getting extremely bright. All the brightness without all the drawbacks. Genius!
Now, one thing I cannot help demystify for you (because I don’t understand it myself) is how the light from one layer of this OLED sandwich passes through with the light of another layer. For that information, I’m going to have to chat with some display engineers familiar with the tech, and I’m already reaching out.
Where has this tech been all these years?
If Tandem OLED is such a bright idea, why haven’t we seen it in a device before? Why isn’t it on TVs and PC monitors? Why haven’t we seen it on a tablet before?
Well, for a couple of reasons, I suspect. I say “I suspect” because I need to verify this with a display engineer, but I think it’s safe to conjecture that, for one, Tandem OLED is clearly fairly expensive to manufacture. If it wasn’t, I’m certain LG Display would be making them in sizes we could put in TVs and PC monitors already. TVs can provide all the power that is needed, but these large-sized Tandem OLED panels are probably just too expensive to put in a TV.
The second reason is that they need more power than mobile devices could deliver – at least until now. The batteries in the tablet or phone would have had to be pretty stout to support the processor and the display for any meaningful amount of time.
And that, my friends, is where Apple’s massive power, paired with its innovation, comes together to bring us the first Tandem OLED displays.
Tandem OLED needed a cash-rich partner to push it into the real world. You don’t make this sort of thing at a small scale — that’s a surefire way to go bankrupt. You need to make display panels at a large scale, and making already expensive new panels at a large scale takes the kind of money very few organizations have — but Apple’s got it.
But you also need a place to put it, and an iPad is the perfect one to put something like an expensive new display. OLED panels start their life as a giant sheet of what’s called mother glass. From this massive sheet of mother glass, you can cut any number of combinations of large and small displays.
For example, you could cut out one 88-inch big screen, and not have a whole lot left over. Or you could cut out three 65-inch diagonal screens and have enough left to cut out six 32-inch diagonal screens.
So you can easily imagine that the yield for something the size of an iPad Pro is going to be exponentially higher than it would be for TVs. Now, it’s still expensive to make, but the yield is much higher, so Apple can recoup a good deal of its cost by building a healthy margin into each iPad.
The other problem only Apple could solve was the power issue. I believe that’s where the M4 chip comes in. The M4 is such an efficient chip that Apple can afford to feed the Tandem OLED display what it needs to create that 1,000 nits of full-screen brightness and 1,600 nits of peak HDR highlight brightness.
But Apple probably did more than that. There were some low luminance efficiency issues Apple’s resources likely helped solve. And who knows what else Apple’s mighty engineering muscle did to make putting a Tandem OLED screen into a device a reality.
Apple created something special
So … while Apple did not invent Tandem OLED, I think it is fair to credit Apple for getting Tandem OLED out of the lab at a display corporation and into a device. And I think we can also credit Apple for making the Tandem OLED screen what it is today.
And now that it is in a consumer device? Well, let’s just say it’s a safe bet that Tandem OLED won’t live exclusively in the iPad Pro for long. When folks get their eyes on the new Ultra Retina XDR, they are going to want that kind of picture quality from every screen they have to look at. That demand will drive the innovation we need to see supply go up and costs go down.
And, believe me, you’re about to get slapped in the face with a bunch of reviews talking about how incredible the new iPad Pro’s Ultra Retina XDR display is. While there are TVs out now that can do 1,600 nits peak HDR brightness, there isn’t a consumer OLED on the market that can do 1,000 nits sustained full-screen brightness.
There are, however, professional mastering displays at use in Hollywood that can deliver that kind of picture – I’ve seen them – and they are nothing short of stunning.
What Apple has done here is a really big deal. The 1,000 nits of average picture level means you can use the new iPad Pro in just about any environment – even outside. And 1,600 nits peak HDR brightness means that the iPad Pro is going to match even the very best TVs on the market in terms of picture quality. And knowing Apple, it might turn out to be the best-looking consumer display on the market. I, for one, can’t wait to get my hands on it.
