QLED vs. OLED (and QD OLED): Which TV Tech Is Right for You?
LG, Samsung, Sony, TCL, and other TV brands use lots of jargon to market their sets. Understanding it can help you find a TV you'll love at a great price.
By James K. Willcox
These can be confusing times for anyone looking to buy a new TV. You’ll have to sort through a mix of 2021 and 2022 TVs at this time of year—with prices at their lowest and highest, respectively—and new technical terms are adding to what was already an alphabet soup of TV acronyms.
These mainly describe the display technology—how the screen is built. You’ll come across four main terms to describe screen types: LED and QLED TVs in one camp, plus OLED and QD-OLED TVs in a second group. They all have advantages, but some of those distinctions are blurring on high-end TVs as manufacturers go on a bit of an innovation spree, introducing more TVs with advanced technologies such as quantum dots and Mini LED backlights to improve picture quality.
If you take some time to sort it all out before buying your new set, you should be able to get a TV you’ll really like, and possibly save some money.
Note, however, that some of the language is really just marketing lingo that makes similar TVs seem more different than they really are. Understanding the newest tech terms can help you decide if you’ll be okay with a leftover model—and lots of those were great sets—or if you should spring for a set with the latest features.
What Are LED and QLED TVs?
Don’t let marketers confuse you: There are only two basic types of TVs—LCDs and OLEDs, which use different technologies.
You’ll see lots of references to LED TVs, but these are really just LCD TVs that use LEDs in their backlights—these days, all LCD sets are built that way.
Here’s how an LCD (liquid crystal display) TV works. Unlike OLED TVs, where each pixel gives off its own light, LCD TVs require a backlight, which shines through a color filter to produce colors. (See the illustration, below.) The backlight is always on, and the liquid crystals act like shutters, opening to allow light in for brighter parts of a scene and closing to block light in dark areas. Some light always escapes, though, which is why black tones on many LCD sets can look grayish rather than truly black.
The term “LED TV” is a marketing construct. The phrase came about nearly a decade ago when companies switched from using fluorescent (CCFL) lamps to LEDs (light-emitting diodes) in LCD TV backlights, mainly because LEDs could get brighter and last longer than fluorescent lamps.
Initially, LED backlights cost more, so some companies saw an opportunity to market these sets to consumers as a new, better type of TV. There were advantages to the technology, but LED sets were really just regular LCD TVs with a different type of backlight. Nowadays, any LCD TV you buy is going to rely on LEDs. At Consumer Reports, we sometimes refer to LCD/LED TVs to help to consumers who have heard both terms. But in our labs, we call them LCD TVs.
LCD TVs consist of several layers, including an LED backlight and color filters. A QLED set replaces the color filter with quantum-dot material.
Source: Samsung Display
That—yes, finally—brings us to “QLED TV,” which is another marketing term. All QLED TVs are also LCD TVs, but they use quantum dots to produce colors.
QLED TVs, from companies, including Hisense, LG, Samsung, and TCL, use a blue LED light source, plus a film embedded with tiny quantum dots, or nanocrystals. The quantum-dot film is sandwiched between the other layers of the LCD panel, replacing the color filter in front of the LED backlight.
When these tiny crystals are hit with the blue light from the backlight, they glow, emitting very saturated primary colors, based on the size and composition of the quantum dot material. Because the size of the crystals can be controlled very precisely, the system renders very accurate colors, even at higher brightness levels where colors can start to look a bit washed-out. So QLED TVs, like LED TVs, are also LCD TVs, albeit fancier ones.
There are two more, newer enhancements to LCDs that you should know about. One is a feature called local dimming, which divides a TV’s LED backlights into zones that can be dimmed or illuminated separately. This can help improve contrast and black levels.
It works best with TVs that have full-array backlights, meaning that there are LEDs across the entire back of the set. However, most LCD TVs on the market are edge-lit sets, with the LED backlights located along the edges of the display. These sets may still use local dimming, but it tends to be less effective, and sometimes result in an effect called blooming, where you see halos of light around bright images shown against dark backgrounds.
TCL 65R635
Local dimming can work especially well in TVs that use Mini LEDs, the latest backlight advancement. By shrinking the size of the LEDs, companies can cram more of them into the backlight. Because the LEDs are so small, you can have many dimmable zones, say 1,000 zones instead of the dozens typically found in even the best LCD sets up until now. And they can be controlled more precisely to help improve contrast and black levels and reduce halos.
Unfortunately, this has created a new set of TV acronyms, as some companies have decided to give sets that use both quantum dots and Mini LED backlights proprietary names. LG, for example, markets its models with these features as QNED TVs, while Samsung has opted for Neo QLED.
These are marketing terms, too, but they can help you determine which sets use these technologies.
What Are OLED TVs?
At Consumer Reports, we’ve been evaluating OLED TVs for almost a decade, and for the past several years they’ve tended to dominate the top of our TV ratings.
As noted above, QLED TVs are just one flavor of LCD television. In contrast, OLED TVs really are different. (OLED stands for “organic light-emitting diode.”) OLEDs are an emissive technology: Each individual pixel gives off its own light, so no separate backlight is required. Because each individual pixel can go from bright to fully off, OLED TVs can generate high-contrast images with truly deep black tones.
Traditional OLED TVs—sometimes referred to as WOLED sets—use a white OLED light source, plus color filters to produce colors.
Source: Samsung Display
Up until this year, all OLED TVs, from companies, including LG, Sony, and Vizio, used a technology called WOLED (though TVs haven’t been sold using that acronym). These sets have a white OLED light source—white is achieved by combining blue and yellow OLED material—plus color filters that produce the red, green, and blue of the color spectrum. You can see the panel structure of this type of TV in the image above.
Sony XR-55A95K
Because color filters absorb some brightness, these sets add a white subpixel that bypasses the color filter to add extra brightness. The downside is that at the very high brightness levels required for some HDR content, that extra white sub-pixel can sometimes make colors look a bit washed-out.
Each year we’ve seen improvements in OLED TV brightness, but in general OLED TVs have still lacked the kind of peak brightness we see in better LCD sets.
LG OLED55C2PUA
What Are QD-OLED TVs?
That desire for extra brightness in OLED sets is where “QD-OLED” TVs come in.
The first two letters stand for quantum dots. Quantum dots had been used only in LCD-based sets, but this year, both Samsung and Sony are offering QD-OLED TVs. QD-OLED TVs represent a hybrid approach that marries the advantages of traditional OLED TVs—high contrast, deep blacks, and unlimited viewing angles—with the higher peak brightness and more vibrant colors you often get with QLED TVs.
QD-OLED starts with a blue OLED light source but uses quantum-dot material rather than a filter to produce colors.
Source: Samsung Display
Just like QLED TVs, QD-OLED sets start with a blue light source and use quantum-dot material to produce red and green light. But because they are OLEDs, the light source in this case is each individual pixel.
Because these TVs don’t use color filters in front of the light source, QD-OLED TVs have the potential to reach higher peak brightness levels without losing any contrast. That, in fact, is what we found in our labs when we tested the Samsung S95B QD-OLED. It had a peak brightness level of over 1,000 nits, making it the brightest OLED TV we’ve ever tested. The Sony A95K, which also used the QD OLE technology, was just below that at close to 1,000 nits. By comparison, the 2022 LG C2 hit 850 nits, bright for an OLED set but below the QD OLED TVs.
While that peak brightness capability was impressive, it didn’t make the Samsung the clear winner in our head-to head testing we did of the 55-inch Samsung and LG sets. (The Sony wasn’t yet available when we did that comparison.) The LG C2 set equaled it in most regards and sometimes offered more natural-looking images. There was just a single point separating the models in Overall Score.
More broadly, the best LCD TVs these days also offer impressive black levels, along with vibrant, accurate colors and bright screens. If you’re shopping for a television, that gives you more top-flight choices than ever before.
Samsung QN55S95B
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