Last Updated on July 13, 2022 by Nachiket Mhatre
For the longest time, the consumer electronics industry had gaslit unsuspecting customers into believing that LCD televisions were better than the CRTs they had replaced. That obviously wasn’t true. But just when everyone began clueing into that lie, TV makers replaced the LCD in LCD televisions with LED.
Not surprisingly, LED TVs weren’t a huge improvement either. Consumers were sold the same crappy LCD technology, but with LED backlights instead of the traditional fluorescent variety.
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Get the latest technology news, reviews, and opinions on tech products right into your inboxIt didn’t take long for that trick to wear thin too. That was the industry’s cue to introduce QLED TVs, which—as you may have guessed by now—were the same old LCD TVs with a plastic sheet full of nanoparticles tacked onto the display panel.
Now, the same folks claim that they have made OLED TVs better with QD-OLED technology. That begs two key questions:
- What is QD-OLED technology?
- Is it actually better than existing OLED technology, or is this yet another ploy to gaslight consumers all over again?
The answer is a lot more complicated than a simple yes or no. In fact, QD-OLED displays can be both better and worse compared to existing OLEDs—all depending on the OLED implementation being considered. Sounds confusing? Well, that’s because it really is. Fortunately, we know just how to break down this paradox.
Let’s take a deeper look at what exactly entails QD-OLED displays and how they are both better and worse compared to different OLED implementations.
QD-OLED vs OLED TV: Which One’s Superior?
Is QD-OLED technology superior to existing OLED displays? The answer is both yes and no. QD-OLED technology is theoretically better than OLED panels used in televisions. However, that isn’t necessarily true once you pit it against OLED panels found in smartphones. Mobile and TV OLED panels, you see, employ vastly different implementations of OLED technology. And the mobile version is undoubtedly superior.
While it is fair to say that QD-OLED TVs are better than plain-vanilla OLED TVs on paper, you can’t conclusively say that QD-OLED panels are superior to all OLED implementations. Because, as of this writing, the OLED displays underpinning flagship smartphones are unbeatable in key areas of picture quality to virtually every commercial, mass-produced display technology in existence.
And although we have answered the primary question, this brings up far more interesting mysteries.
For starters, what’s the need for two separate OLED implementations for smartphones and televisions? Secondly, why are the more expensive OLED TVs saddled with a relatively inferior technology compared to their smartphone counterparts? And finally, where does QD-OLED sit in this confusing pecking order of display technologies?
Why Are OLED TV And Smartphone AMOLED Panels Different?
The average smartphone OLED panel is fairly uncomplicated. The individual pixels in these emissive displays not only generate the image but also serve as discrete sources of light. Each OLED pixel can recreate colours from a palette of several million by the virtue of modulating the intensity of the individual red, green, and blue subpixels.
As far as display technologies go, this is unequivocally the holy grail of picture quality. But it comes with a few significant issues.
The O in an OLED pixel stands for organic. This is a problem because, like all carbon-based semiconductors, OLEDs have a limited shelf life. Worse yet, the individual red, green, and blue OLED subpixels tend to age at different rates. The blue subpixel, in particular, ages relatively more rapidly, which eventually manifests as a colour shift in all OLED panels. However, the inevitable colour shift won’t become apparent for a few years.
That’s fine for smartphones, which are replaced every few years, but people tend to hold on to their television sets for much longer. Moreover, it’s also more expensive to manufacture OLED displays with three discrete subpixels.
Most smartphones get around this problem by sharing subpixels with adjacent pixels. Samsung’s trademark PenTile OLED matrix—employed in most of its AMOLED panels—reduces the number of blue and red subpixels by doubling the green subpixel count. This works out fine because the human eye is more sensitive to green, but this workaround comes at the cost of reduced display sharpness.
Unfortunately, this approach is still not feasible for televisions. The aforementioned OLED panels are notoriously expensive to manufacture for tiny smartphone screens. Using the same technology on significantly larger TV screens is therefore out of the question.
OLED TVs Must Cheat To Maintain Competitive Pricing
Samsung had, in fact, ported the same discrete RGB subpixel OLED technology on a one-off OLED television. Unsurprisingly, it was too expensive to make much commercial sense. Interestingly, LG has been the only display manufacturer to make commercially viable OLED TVs. And the way it has achieved this seemingly impossible feat is rather interesting.
LG’s unique approach to OLED panels for televisions utilises four subpixels—red, green, blue, and white. The white subpixel allows LG OLED panels to appear brighter due to the way the human eye perceives luminance. This is a brilliant hack that allows LG to increase the perceived brightness of the TV without driving the organic semiconductors at higher voltages, which can decrease the panel’s lifespan.
However, LG’s solution to the OLED colour shift problem is even more ingenious.
The shift occurs over time as the red, green, and blue OLED subpixels degrade at varying rates. LG’s TV OLED panels work around this problem by doing away with traditional OLED subpixels assigned to the three primary colours. Unlike smartphone OLED panels employing discrete red, green, and blue subpixels, LG’s TV OLED panels use a sandwich of blue and yellow OLED elements to create pure white light.
This light is then passed through red, green, and blue colour filters to separate it into corresponding red, green, blue, and white subpixels. This approach is brilliant because it minimises the impact of OLED degradation by reducing the count of OLED emitters from three (red, green, blue) to two (blue and yellow). An OLED subpixel composed of a uniform OLED element, as opposed to having three separate colours, is inherently more reliable.
This matters because OLED subpixels are semiconductor elements subject to manufacturing defects. A design with simpler semiconductor elements has a much higher manufacturing yield as a consequence. In effect, this approach makes TV OLED panels cheaper, brighter, and more durable.
No wonder, LG was the sole supplier of OLED panels to virtually all TV manufacturers until Samsung introduced its QD-OLED alternatives.
LG’s OLED TV Compromise Isn’t Without Consequences
There are no free lunches, and that adage applies to display technology as well. The colour filters used to split individual white OLED pixels into white, red, green, and blue subpixels in LG’s OLED panels might save cost, but this comes at the cost of the overall picture quality.
These colour filters aren’t 100 percent efficient. They block some amount of light while selectively filtering out the three primary colours making up the subpixels. Not surprisingly, this reduces the overall brightness. Worse yet, the fourth white subpixel, designed to increase the perceived brightness, also ends up making the colours appear washed out as a side effect.
Although this phenomenon can be mitigated by dialling up the colour saturation values, a TV OLED panel cannot match the saturation levels of its mobile counterpart. This is yet another reason why OLED TVs cannot match the HDR capabilities (learn more about HDR in our comprehensive guide) and brightness of modern HDR-capable LCD televisions.
The colour filter also leads to relatively worse viewing angles. The light-emitting pixels on mobile OLED panels are unobscured, which allows them to be viewed from virtually any angle without any colour shift or loss in image quality. This changes when you stack an additional layer of optical material on an OLED TV. The colour filter adds a parallax barrier that slightly reduces the optimal viewing angles for OLED TVs.
The viewing angles aren’t as bad as LCD televisions, but it’s definitely narrower compared to mobile OLED panels devoid of colour filters.
QD-OLED vs OLED TV: What’s the Difference?
The QD in Samsung’s brand new QD-OLED panels stands for quantum dots. This is the magic sauce that replaces the colour filters employed in LG’s OLED TV panels and promises to solve its aforementioned limitations. To oversimply the concept, QD-OLED technology is quite similar to Samsung’s QLED—except, the quantum dot layer is slapped onto an OLED panel instead of a traditional LCD.
Samsung’s QD-OLED replaces the blue/yellow composite OLED pixels found in LG’s OLED implementation with monochromatic OLED pixels generating pure blue light. But instead of passing this light through colour filters like LG OLED TVs, Samsung’s QD-OLED panels harness this light to power the red, green, and blue subpixels with the magic of an additional quantum dot layer.
Knowing how quantum dots work is key to understanding this technology. These semiconductor particles are really tiny and measured in the order of nanometres. Quantum dots are special nanoparticles designed to absorb energy from any light source and convert it to monochromatic light. The frequency of the emitted monochromatic light depends on the particle size.
In other words, smaller quantum dots measuring at two nanometres emit high-frequency colours such as blue. On the other hand, quantum dots that are twice as large emit lower-frequency hues such as red. This allows display engineers to generate extremely pure monochromatic light sources by controlling the size of nanoparticles in the quantum dot layer.
That explains why the quantum dot layer in Samsung’s QD-OLED displays makes up the RGB subpixel arrangement. Each subpixel utilises the blue OLED light to excite the quantum dots and emit monochromatic light in the hue that corresponds to their size. That’s how the subpixels in a QD-OLED display emit the purest form of red, green, and blue light to reproduce accurate colours.
QD-OLED vs OLED TV: What Picture Quality Improvements To Expect With QD-OLED?
- Improved Brightness and HDR Capability
- Better Colour Accuracy
- Richer Colour Saturation
- Better Viewing Angles
- Potentially Cheaper When the Technology Matures
We have learned how Samsung’s QD-OLED technology differs from LG’s OLED TV implementation. Furthermore, we also know exactly how it works. Although there aren’t too many QD-OLED TVs out in the market as of this writing, a bit of common sense goes a long way to verify Samsung’s claims of superior picture quality over traditional OLED TVs.
1. Improved Brightness and HDR Capability
Traditional OLED TVs lose a significant amount of brightness thanks to their use of colour filters that are inherently inefficient at light transmission. QD-OLED panels, however, have nothing obstructing the emissive (light generating) quantum dot layer. Samsung’s technology is especially clever in the way it enhances the luminance efficiency of the panel.
The primary OLED emitter is blue by design to improve display brightness and colour saturation. That’s because blue has the highest frequency of all colours in the visible light spectrum, which also allows blue light to carry the most amount of energy. A high-frequency light source is naturally more efficient at exciting the nanoparticles, which causes the QD layer to light up the individual subpixels brighter as a consequence.
It’s safe to say that for the same amount of power consumed, on paper, a QD-OLED panel will be brighter compared to a traditional OLED TV panel.
2. Better Colour Accuracy
Adding manufacturing complexity to any display technology makes it more susceptible to colour reproduction issues. LG’s OLED TV technology relies on creating white light, which is then filtered into individual red, green, and blue subpixels. In reality, it is extremely difficult to produce pure white light. Any deviation from pure white manifests itself as colour inaccuracy.
Samsung’s QD-OLED panel, however, relies on pure blue OLED emitters to generate monochromatic light. Furthermore, this light energy is converted into red, green, and blue pixels using nanoparticles. These quantum dots emit extremely pure monochromatic colours defined by the size of the nanoparticles. The very laws of physics ensure accurate colour reproduction and a wide colour gamut in QD-OLED TVs.
3. Richer Colour Saturation
LG’s OLED technology employs an additional white pixel to increase the perceived brightness. But this has an unfortunate side effect of washing out colours. That’s why traditional OLED TVs appear washed out under bright lighting, whereas the same issue isn’t evident in AMOLED smartphones employing a pure RGB subpixel arrangement.
4. Better Viewing Angles
Mind you, regular OLED TVs have great viewing angles that are significantly better compared to LCD TVs. However, the presence of colour filters in the panel creates a parallax barrier that slightly impairs viewing angles and results in a minor colour shift. For all practical purposes, this won’t even be evident unless you’re looking at the TV from extreme angles.
5. Potentially Cheaper When the Technology Matures
LG had managed to bring down the cost of OLED panels by reducing the number of individual OLED emitters required from three discrete emitters to two sandwiched emitters. Samsung’s QD-OLED panels, however, bring that number down to a single blue OLED emitter.
Given how costly it is to manufacture OLED emitters, QD-OLED TVs are expected to become cheaper than traditional OLED TVs as the technology matures and associated semiconductor fabrication yields improve.
Should You Buy a QD-OLED TV?
Currently, that entirely depends on where you live. As of this writing, Samsung has launched a few QD-OLED models in the continental US. However, their availability elsewhere in the world is spotty at best. The low reported yield rates, as expected from any new display technology, have pushed prices of 55-inch and 65-inch QD-OLED TVs anywhere between $2,200 and $3,500.
The technology is indeed superior to OLED TVs on paper, but it’s also important to note that the improvement in picture quality will roughly be comparable to that between an OLED TV and the AMOLED screen of recent flagship smartphones. Don’t expect to notice a difference unless you compare the two technologies side by side.
Even if you don’t mind paying a premium over existing OLED TVs, we recommend waiting for wider media coverage and more comprehensive user reports before jumping all in.
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