Samsung is one of the most recognisable brands in the world, with many of its products leading the way in their respective markets. 

One such example is 'QLED' TVs, which have strengthened the company's position as the most popular television brand worldwide.

However, despite the similarity in name, this is very different from the OLED technology that most other brands offer. In this article, we'll explain the difference between the two, as well as what effect this might have on the user. 

What is QLED and OLED?

Let’s start with OLED. It stands for organic light emitting diode. OLED TVs are emissive which means that each pixel emits its own light. If a pixel is turned off, it emits no light and is therefore black. This is how OLED TVs can offer their “infinite” contrast ratios and why their blacks are so deep.

So-called LED TVs are actually LCD TVs. When flatscreen TVs first went mainstream a number of years ago, the LCD panels were powered by fluorescent tubes. This consumed a huge amount of energy relative to output, so they have since been replaced with the much more energy-efficient LEDs.

However, there has been little change to LCD display technology since then, hence why many manufacturers have moved to OLED panels. As the pixels themselves don't emit light, the LEDs shine from the side of the display or behind it in order to show the picture. This is why you can buy TVs which are 'LED backlit' and 'LED edge-lit'. The vast majority are the latter, a variation of which Samsung has included in its latest QLED TVs.

The 'Q' in this case refers to Quantum dot. But what is Quantum dot?

There are undoubtedly similarities to the LCD technology described above, 

Yet, the LCD technology which creates the picture you see has remained pretty much the same. The pixels don’t emit any light, so LEDs are shone through either from behind or from the side so you can see the picture, a bit like shining a torch through a piece of paper. And this is why some TVs are called ‘LED backlit’ and ‘LED edge-lit’.

Most LCD TVs are edge-lit, and this includes last year’s Samsung QLED TVs. The Q, as you may have guessed, stands for Quantum dot. So what is quantum dot?

It’s a bit like OLED because the tiny molecules (the quantum dots) emit coloured light when light is shone on them. These quantum dots are contained in a film which forms just one of many layers which makes up a QLED TV. Others include a prism sheet which helps to improve viewing angles, diffuser sheets and polarisers.

QLED vs OLED: tech explained

In short, a QLED TV is an LCD TV with an added quantum dot layer that improves brightness and colour compared to ‘standard’ LED LCD TVs. The brightest current models can output around 1400 nits: the average LCD TV peaks at 300-400 nits. OLEDs, such as the LG C7, can hit just over 700 nits.

Both acronyms - OLED and QLED - are essentially umbrella terms which encompass variations in the technology. Not all OLED TVs are identical in their architecture and neither are QLED TVs, although QLED is more of a marketing term than OLED.

Here's what Samsung thinks the benefits are:

Is QLED better than OLED?

When the technology was emerging you might have said no, but it's a different situation now. One of the disadvantages of OLED is that it isn’t as bright as the brightest LED TVs. Manufacturers are chasing ever higher brightness so their TVs can produce more contrast and therefore a better image when playing HDR video, but another advantage of Samsung’s QLED tech is better colours.

Samsung calls this ‘100% colour volume’, but it simply means more saturation and therefore vivid colours. The company's displays have always tended to produce saturated colours, which the above video explored in detail. Whether you like such an eye-catching display will come down to personal preference. 

However, a potential issue when using the edge lighting technology in a QLED TV is the potential haloing at when you reach a high brightness. This refers to the image looking like it is following itself around the screen, or edges looking blurry as opposed to being 

With Samsung QLED TVs regularly exceeding 1000 or even 2000 nits, this has the potential to cause problems over time.

However, the company has taken steps to ensure this does not become a widespread issue. Some of its more modern TVs use backlighting, which don't suffer from the problem to the same extent. 

Samsung has also released software specifically designed to figure out where the bright areas are and dim them in line with the rest of the display. ensuring a more consistent image free from haloing. 

All in all, the steps taken mean it shouldn't be too much of an issue. 

Which one should I buy?

This is the hard part. We’ve yet to test out the most recent models, but judging by past performance we'd have to give the edge to QLED. While the ultra-vibrant display is not for everyone, the level of detail and range of colours is superb.

However, choosing which TV to buy should not come down to just image quality. Price, software features, aesthetics and sizing should all play a big role in which TV you buy.

While OLED and QLED TVs were once incredibly expensive, the technology is becoming much more affordable as the focus shifts to 8K. Nowadays, you can pick up an excellent 4K TV for just a few hundred pounds. 

Samsung’s latest QLED look set to go head-to-head with the latest OLED TVs for many years to come. A QLED TV currently sits top of our best TV chart, but it remains to be seen how long it can stay there.