What is QD-OLED? The hybrid TV tech fully explained | Digital Trends

What is QD-OLED? The hybrid TV tech fully explained | Digital Trends

What do you get when you cross a QLED TV with an OLED TV? No, this isn’t just the setup to some silly punchline, but an actual TV tech amalgamation that’s called QD-OLED. This acronym decoded stands for “Quantum Dot Light Emitting Diodes,” and it’s the reason QD-OLED TVs have been some of the best TVs money can buy over the last few years.

It’s the kind of picture quality you genuinely have to see to believe. Thanks to the layer of quantum dots built into the self-emissive OLED screen, a QD-OLED is able to deliver a wide color gamut and intense brightness levels, especially when watching HDR movies and shows. But because a QD-OLED doesn’t actually contain any backlighting (like you’d find on a traditional QLED TV), the millions of self-emissive pixels allow the QD-OLED to achieve the kind of inky black levels you’d expect to see on any OLED TV.

QD-OLED TVs and monitors are still relatively new, though TV brands like Samsung and Sony are already a few years in on this fantastic picture technology. That being said, we thought we’d put together this explainer to walk you through the ins and outs of QD-OLED tech.

What is QD-OLED?

Simply put, QD-OLED is a hybrid display technology that takes the already very impressive qualities of OLED TV and improves its brightness and color through the use of quantum dots.

PlasmaChem / PlasmaChem

The result is a TV that exhibits the stunning levels of contrast and perfect blacks of OLED while delivering brightness levels that exceed anything we’ve seen from OLED so far.

This “best of both worlds,” benefit was largely theoretical until we got a chance to see it for ourselves at CES 2022. Those impressions survived even once we brought the first two QD-OLED TVs in for testing: first with the Sony A95K, and then again with the Samsung S95B. Both TVs earned a rare 10/10 rating from our TV guru, Caleb Denison.

Fast forward to 2024: After the success of the Samsung S95B QD-OLED, the company would go on to release the 2023 S95C and this year’s model, the Samsung S95D. Sony has also released a Gen 2 version of its QD-OLED tech, billed as the Sony Bravia Series XR A95L. We’ve actually been able to test both of these QD-OLED TVs, and we were completely blown away by what each brand chose to bring to the table for 2024. 

Picture improvements aside, it’s also possible that over time, QD-OLED TVs may prove less expensive to buy than similarly sized OLED TVs. We’ll discuss this in more detail later. Since QD-OLED TVs are essentially an evolution of OLED, it’s expected that some of the clever things we’ve seen LG do with its OLED panels, like transparent displays and rollable displays, could be possible with QD-OLED models, too.

How does QD-OLED work?

To understand the inner workings of QD-OLED, we need to quickly explain the differences between QLED and OLED.

QLED TV

A diagram of an LCD-based display.
Samsung Display / Samsung Display

QLED TV uses four main elements to produce its pictures: An LED backlight, a layer of quantum dots, an LCD matrix, and a color filter.

The LED backlight produces all of the brightness you see — and modern LED backlights can produce a lot of brightness, far more than OLED light sources. But achieving that brightness while maintaining a full-spectrum white, is difficult.

The solution: Start with a really bright blue LED light source, then use red and green quantum dots to balance the blue into a full spectrum of white. Because quantum dots can be tuned to emit specific colors and, amazingly, can do this at a nearly 100% efficiency level, QLED TVs get a much-needed improvement to their color accuracy without sacrificing any brightness or needing to use more energy.

From there, the purified white light passes through the LCD matrix (which is responsible for the images you see, and how bright or dark areas of the screen are) and, finally, through the color filter, which converts the white light into the right amounts of red, green, and blue so that we see true color images.

The Samsung S95C OLED in a living room.
The Samsung S95C QD-OLED. Douglas Murray / Digital Trends

It’s a good system that produces bright and very colorful images. It’s also quite affordable to produce because, except for the quantum dots, all of the components have been around for decades, and are now “cheap” to make.

But it has drawbacks, too. No matter how hard the LCD matrix tries, it can’t block 100% of the light from coming through in dark scenes, so you never get that perfect, inky black that you see on an OLED TV. The LCD matrix also creates problems for off-angle viewing because it tends to “tunnel” light straight outward from the screen.

QLED also has to use more energy to create the brightness you see because the combination of the LCD matrix and the color filter diminishes the light the LED backlight generates. This makes QLED TVs less energy efficient than OLED TVs.

Finally, and this may only matter to decor-oriented TV buyers, all of those elements add up to a thicker overall TV panel.

OLED TV

OLED TV uses an OLED light source and a color filter to produce its image.

That sounds remarkably simple compared to QLED TV, and it is. Thanks to the emissive nature of the basic element of OLED TV — the OLED pixel — this one ingredient can take care of brightness and image creation, essentially fulfilling the roles of both the LED backlight and the LCD matrix in QLED TV.

Without an LCD matrix, viewing angles with OLED TVs are as near-perfect as we’ve ever seen. You can sit wherever you like and still see the same levels of brightness, contrast, and color.

And as we’ve already hinted, because OLED pixels can be shut off completely when an image calls for perfect blackness, that’s exactly what you get: No light being emitted at all.

But OLED TV isn’t perfect either. You can only derive so much brightness from an OLED pixel. It’s excellent in low-light conditions, but it simply can’t compete with QLED’s dedicated LED backlight in brighter environments. If you’ve ever looked at a QLED and OLED TV side by side in a brightly lit Costco warehouse and found the QLED TV more appealing, it’s probably due to its superior brightness.

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LG G4 OLED
Zeke Jones / Digital Trends

OLED TV brightness is lower than QLED for two main reasons. First, and most importantly, each OLED pixel creates its own light. But the more power you drive through an OLED pixel, the more you shorten its lifespan. So OLED TVs could probably get brighter than they do today, but few buyers would be OK with a TV that only lasted half as long. The LEDs used in a QLED TV’s backlight are far less susceptible to this kind of aging and can continue to produce lots of light for a long time.

Second, no matter how much light an OLED pixel can create, some of that light will be absorbed by the color filter.

OLED panels are also susceptible to something known as burn-in. If you display the same kind of content on an OLED TV for tons of consecutive hours — say a lower info banner on a news channel or a control panel in a video game — it can cause those pixels to age at a faster rate than the pixels that are constantly displaying different images.

The residual “shadow” of that static content is called burn-in, and once it happens, it’s usually permanent.

Finally, because the large-format OLED panel market is effectively a monopoly, with just one company — LG Display — manufacturing and selling them to companies like LG, Sony, Philips, and Vizio, it will remain more expensive than QLED for some time to come.

QD-OLED: Busting the brightness barrier

So the question that faces the TV world is, how can you hold on to all of OLED’s many benefits and improve on its weaknesses?

The solution is QD-OLED, also referred to by some companies as “QD Display.”

Quantum Dot OLED significantly increases the overall brightness of OLED — and even improves its already superb color — by optimizing how much light a single OLED pixel can emit and eliminating the color filter.

Here’s how it works.

Why start with white?

At the moment, OLED TVs create their light and color starting point with white light. They do this by combining blue and yellow OLED material to create a blend that comes very close to pure white. Why do this instead of using red, green, and blue OLED material? The answer has to do with the complexities of manufacturing OLED panels at the 50-inch to 88-inch sizes of today’s TVs while keeping costs as low as possible.

To give you a sense of just how expensive a true RGB OLED panel is, Sony used to make a 4K, 55-inch monitor for the broadcast and film industries that used this technology. It cost nearly $28,000, although the model has since been discontinued, and it doesn’t look like Sony has any plans of introducing a next-gen successor anytime soon. 

But when you start with white light, you need a way to separate the individual red, green, and blue portions of the spectrum. A color filter does this admirably, but color filters, as we mentioned above, reduce brightness.

A diagram of a WOLED display.
Samsung Display / Samsung Display

LG’s technique for regaining some of the brightness lost to the color filter involves the use of a white subpixel that bypasses the color filter.

When you’re watching standard dynamic range (SDR) content, the use of that white subpixel is moderate. OLED TVs can easily get bright enough to meet the full specification for SDR without relying heavily on the brightness of the white subpixel.

“Displays of all types that use this architecture are able to achieve color accuracy at relatively lower luminance,” said Jeff Yurek, director of marketing and investor relations at Nanosys, a company that develops quantum dot technology. But HDR material is a bit trickier.

When viewing HDR content, the panels turbocharge these white subpixels to deliver HDR’s higher brightness. But there’s a limit to how hard you can drive those white subpixels. Push them too far and not only do you reduce the panel’s life, but that extra brightness can also wash out the color of the other subpixels, something that is especially noticeable when displaying small features like text, which can often look less crisp.

Back to blue

To deal with the technical hurdles of OLED brightness, QD-OLED TVs take a page out of QLED TV’s handbook. Using the same principle that lets a QLED TV turn a blue backlight into a pure white light using red and green quantum dots, a QD-OLED panel uses just blue OLED material as the basis of each pixel.

That blue OLED pixel is then divided into three subpixels: A blue subpixel, which is the original blue OLED material, left unchanged; a red subpixel that layers red-tuned quantum dots over blue OLED; and a green subpixel that layers green-tuned quantum dots over blue OLED.

A diagram of a QD (QD-OLED) display.
Samsung Display / Samsung Display

Since quantum dots are so energy-efficient, virtually no brightness is lost in those two color transformations. The result is a true RGB OLED display without the cost and complexity of a discrete RGB OLED starting point, the brightness tax of a color filter, or the need for a color-sapping white subpixel.

“What is so exciting about QD-OLED displays,” Yurek said, “is that they do not require a white subpixel to reach peak luminance. QD-OLED will be able to express the full color volume from near black all the way up to full-peak luminance without compromise.”

QD-OLED: more affordable?

It may take several years, but it’s possible that QD-OLED TVs will end up costing less than OLED TVs to make. Getting rid of the color filter is a great way to reduce materials and manufacturing complexity, which should mean a smaller outlay of cash.

And since QD-OLED will theoretically be brighter than OLED without the use of more electricity, it might be possible to create QD-OLEDs that have the same brightness as OLEDs while using less energy. Lower energy use brings down the cost of many of the components that have to be engineered to handle higher energy loads.

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This all assumes that the investments needed to make QD-OLED manufacturing a reality will be paid off quickly, but that’s far from certain at this point.

Having your (OLED) cake and eating it, too

Blue OLED material — the light source of QD-OLED displays — is a notoriously tricky substance to work with.

Much like other OLED materials, there’s a three-way trade-off between lifespan, brightness, and efficiency. Generally speaking, any time you prioritize one of these attributes, the other two suffer. Drive an OLED pixel hard enough to produce the brightness you want and you not only diminish its life expectancy but also its efficiency.

But QD-OLED displays may prove to be the exception to this rule. By using three layers of blue OLED material per pixel, each layer can share the brightness burden.

“The amount of power needed from the blue OLED pixel in the QD-OLED to produce a given amount of front-of-screen brightness will be less,” said Jason Hartlove, CEO and president of Nanosys.

Who makes QD-OLED TVs?

Samsung 2023 S95C QD-OLED TV seen in a brightly-lit room near windows.
Samsung / Samsung

At the moment, Samsung Display — a division within Samsung that develops display technologies but doesn’t sell final products like TVs or monitors — is the only company manufacturing QD-OLED panels. It sells these panels to companies like Sony, Dell’s Alienware division, and Samsung Electronics (the Samsung division that makes and sells TVs). We expect other companies will join the ranks of Samsung Display’s QD-OLED customers now that we’re a couple of years into this TV tech.

We’re confident that there will eventually be many companies selling QD-OLED TVs, but for now, it looks like Sony and Samsung are alone in this new field.

When will QD-OLED TVs be available to buy?

You can buy QD-OLED TVs right now, from Samsung and Sony, but as we mentioned up above, you may not realize it because of the way each company names its products.

For instance, Sony’s current QD-OLED is called the Sony Bravia XR A95L 4K HDR OLED TV on Best Buy’s website, yet it’s clearly labeled as a QD-OLED on Amazon (go figure). Over on Samsung’s side of the field, both the S90D and S95D QD-OLEDs are labeled as straight-up OLEDs through Amazon and Best Buy. Stop perplexing us, guys! These acronyms are confusing enough.

You can purchase the Samsung S95D model in 55, 65, and 77-inch sizes. The Samsung S90D is actually available in more sizes than the flagship S95D, including 42 inches, 48 inches, and an 83-inch option. As for Sony, the XR A95L is available in 55, 65, and 77-inch sizes. 

How much do they cost?

Samsung’s QD-OLED TVs cost considerably less than Sony’s, though as Senior Editor, Caleb Denison, points out, most people wouldn’t be able to appreciate the subtle improvements that Sony offers. This makes Sony’s price premium difficult to rationalize.

The Samsung OLED 4K Smart TV S95D starts at $2,600 for the 55-inch model, while the 65-inch version costs $3,400. Those are full MSRP prices though, and we’ve seen both the S90D and S95D models receiving some big discounts. In fact, as it stands, you can purchase the 65-inch S95D on Amazon for $2,800. As for the 77-inch S95D, full retail is $4,600, but it’s currently marked down to $4,100.

If you’d rather go for the Samsung S90D, pricing starts at $2,000 for the 55-inch model, which we’ve already seen as low as $1,400. The 65-inch version retails for $2,700, with prices as low as $1,700, and the 77-inch size retails for $3,700, but has gone as low as $2,600!

For its part, Sony sells the 55-inch Bravia XR A95L for $2,700, but we’ve seen it on sale for as low as $2,500. There’s also the 65-inch for $3,500, which we’ve seen as low as $3,300. Not only are these regular prices much higher than Samsung’s, but the discounts we’ve seen are also less exciting — only about $300.

Is QD-OLED the last word in TV technology?

Nope! Nothing halts the progress of technology, and the companies that manufacture quantum dots have their sights set firmly on the eventual domination of the TV landscape.

QDEL sounds like the holy grail of TV tech, doesn’t it?

Remember when we said that quantum dots use light energy at almost 100% efficiency to produce their own light? Well, it turns out that quantum dots aren’t picky about their diet. They can also be energized using electricity for what’s known as quantum dot electroluminescence, or QDEL. According to our friends at FlatPanels HD, at CES 2023, certain lucky parties were given a closed-door look at a six-inch QDEL-powered Nanosys device. 

Right now, Nanosys is referring to this revolutionary quantum dot prototype as a “NanoLED” display, and these electrically charged dots should result in much thinner, brighter, and far more energy-efficient TVs down the line. 

MicroLED TVs are also becoming potent, if pricey, alternatives for the home display market. Their modular design means that their key strength is being able to scale from as small as 76 inches to well over 16 feet, but they’re also incredibly bright while possessing black levels and color accuracy to match QD-OLED TVs. But for now, they remain bulkier, are more expensive, and pack lower resolutions per inch than any other display technology.

Samsung currently makes a 110-inch, 4K microLED TV, but it doesn’t sell the product directly to buyers or through retail stores like Best Buy. Instead, you have to contact a Samsung-licensed AV installer. And if you have to ask how much it costs, well … you know how that one goes.

Still, just like QD-OLED, OLED, and plasma, it’s expected that microLED will soon become more affordable, more adaptable, and available in sizes that the average buyer might want.











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