It doesn't seem too long ago that we were questioning whether OLED TV would really take off, but since then many ultra-thin screens have passed through our testing rooms. Our verdict? OLED TVs were definitely worth the wait.

With the rapid evolution of televisions over the past few years, we've seen new technologies from Smart content to 4K Ultra HD resolution to HDR all become established features. OLED has managed to work its way on to the long list of TV jargon too, with its main selling point being ultra-dark blacks and super-bright whites.

The first OLED TVs started to hit the shelves in 2013 but they were both few and far between, and expensive. These sets gave us a glimpse at what all the fuss was about, with a revolution in picture quality and slimline design promised - a 4K OLED TV became the holy grail in many AV enthusiasts' minds.

But that promise appeared to wane somewhat during 2014. First there was news that Sony and Panasonic had ended an OLED TV production partnership in order to focus on 4K Ultra HD TV production, and at CES that year LG was the sole manufacturer to show off a new range of OLED models.

LG was once again the only manufacturer to produce OLED TVs in 2015 as Samsung said it would rather concentrate on 4K LCD screens. The first curved 4K OLED TV passed through our doors and exited with a glowing five-star review.

But now, finally, we have not one but five OLED TV manufacturers in the UK: LG, Panasonic, Sony, Philips and Loewe. Samsung, meanwhile, is backing a different horse: QLED. Don't confuse QLED with OLED, though - they're two completely different TV technologies (for more, read our complete guide to QLED).

The initial problems with OLED - cost and yield rate - have started to improve, so now is a better time than ever to buy an OLED TV. But how does OLED technology work, what's so good about it and which are the best OLED TVs to buy? Let us explain. 

MORE: See all our OLED TV reviews

What is OLED TV?

OLED – or Organic Light-Emitting Diode – is a type of display technology that makes it possible to create even slimmer TV sets than LCD or plasma, while at the same time making them more efficient and eco-friendly. To give you an example of just how slim, there's this LG wallpaper OLED that is just 0.97mm thin.

Here’s how the technology works: an organic, carbon-based film is placed between two conductors and an electrical current is passed through, which causes it to emit light. This differs from LCD TVs, which require a backlight to create their brightness. OLED pixels are self-emissive and generate their own light.

There are two types of OLED technology: Passive-Matrix (PMOLED) and Active-Matrix (AMOLED). Active-Matrix requires electronics to switch each pixel on or off individually, which is better for displaying motion and therefore the type used for OLED TVs.

Initially, only two manufacturers launched OLED TVs in the UK – LG and Samsung (the latter back in 2013). Samsung later bowed out of OLED production, leaving the market to LG.

Panasonic, Sony, Philips and Loewe have all since entered the fray. Sony's A1 range of 4K OLED TVs was announced in January, while Panasonic recently announced two new ranges of OLED TV for 2017.

Hisense has created its own alternative ULED technology, and Samsung has also gone its own way with QLED. They might sound quite similar to OLED, but they're completely different beasts.

MORE: TV tech explained: Quantum Dot, SUHD, HDR, Dolby Vision

What are the advantages of OLED TV?

OLED technology has several advantages over LCD and plasma technology. First there are the physical benefits – OLED sets are lighter and thinner than LCD due to the lack of a backlight.

But of greater interest is the picture quality. Because OLED pixels emit light directly, viewing angles tend to be much wider, plus colour and contrast stay the same from as far as 90 degrees off centre.

And because each pixel can be turned off individually, OLED TVs can do their best to deliver an absolute black and infinite contrast ratio – the Holy Grail for purists. OLED pictures should also be brighter and can achieve response times of less than 0.01ms, which practically eliminates motion blur. 

MORE: Panasonic EZ952 is firm's second 4K OLED TV, arrives in June

What are the disadvantages of OLED TV?

OLED is extremely expensive to produce, and therefore to buy - LG’s first 55in set, the 55EM970V cost £10,000 at launch and its 55EA980W sold for £8,000. Samsung’s first set, the KE55S9C, sold for £7,000. Prices have thankfully come down, though - witness the LG OLED55B6V for under £2,000.

In its infancy, OLED production had a relatively low yield, which meant that for every set fit for sale, a high number were consigned to the scrapheap. This made the technology expensive - it's improving this aspect of the production, which helps to bring costs down.

Of course, there are still some mega-expensive sets around. The LG OLED65G6V is an anomaly at £6000, while Loewe's first OLED screen is targeted at the very wealthy.

Another of OLED’s problems concerns the pesky blue pixel. Because the OLED material used to make blue light deteriorates more quickly than red and green, its lifespan is shorter and, over time, the colour balance could be affected. 

Thankfully, based on recent OLED TVs, the sets are definitely getting better - and more affordable.

MORE: LG Display increases 4K OLED yield to 65%

More after the break

What about curved OLED TVs?

The first OLED TVs launched in the UK by Samsung and LG featured curved screens. There has been much scepticism over this – indeed we saw it as both a plus and a minus in our review of the first Samsung curved OLED TV.  

“It’s an outlandish idea,” we said, “not unlike a concept car: it’s very cool, even if it might not be entirely practical”. The curve also means Samsung’s set can’t be wall-mounted.

The argument in favour said that a curved set enhanced the viewing experience. Samsung said it provides “depth to the content displayed for a more life-like viewing experience”, and delivers an “immersive panorama effect". LG has said the curve is there to “remove the problem of screen-edge visual distortion and detail loss”.

But that was then. Since, manufacturers' enthusiasm for curved OLED TVs has cooled somewhat. At the start of 2017, LG and Sony announced they won't make any curved TVs this year, OLED or otherwise. So it seems curved TVs, like 3D TVs before them, have been consigned to the dustbin of history.

Fortunately, there's no shortage of non-curved OLED sets around. Those who prefer their telly flat would be advised to check out the LG OLED65E6V, Panasonic TX-65CZ952B or one of the other recommended sets at the end of this article.

For our money, a curved screen makes more sense on a phone - like the LG G FlexG Flex 2 or Galaxy S6 Edge - than on a TV. Find out why we think so here.

What about flexible OLED TVs?

And if that wasn't enough from LG, the company has also developed bendable OLED screens, one of which it showed off recently. Known as the Wallpaper TV, due to its ultra-thin design and the fact that it sticks to your wall using magnets, the LG Signature OLED W7 is a veritable wobble board of a set.

Check it out.

What's the point? We're not entirely sure. You could move the TV from wall to wall very easily, though most people will opt to leave it in the same place. But you can't deny that it's a technological marvel, standing just 0.5cm thick and weighing only 12kg.

LG has also unveiled similar technology on a much bigger scale for advertising screens. And it's doubling its production of OLED and flexible OLED panels, which should hopefully bring the price down for us punters. So while the Wallpaper TV might be a spectacle, it probably won't be a novelty one-off...

MORE: LG predicts bright future for OLED TVs as plasma faces final curtain

What about 4K HDR OLED TVs?

Not content with the introduction of OLED as a standalone option, LG introduced the first 4K OLED TV. The combination of 4K resolution and OLED screen technology was seen by many to be the ultimate TV. And going by the first sets we saw, that was certainly true.

But now there's a new abbreviation to make picture performance even better. High Dynamic Range, or HDR, isn't exclusive to OLED TVs, but it can improve and enhances the detail in whatever you're watching. 4K OLED TVs with HDR include the stellar LG OLED65E6V, Panasonic EZ1002 and its follow-up EZ952 (due to arrive in June), and the upcoming Sony A1 Series.

We'll bring you reviews of these as soon as we can. But from our demos, they look stunning.

MORE: 4K Ultra HD: everything you need to know

MORE: HDR TV - What is it? How can you get it?

What about alternatives to OLED TVs?

While it's true that OLED TVs produce some of the best pictures we've seen, there are other TV technologies that lay claim to equally impressive results. 

One such is Quantum Dot. It's not a new technology, but it's finally being adopted by the big manufacturers. It uses nano-crystals that each emit different colours depending on their size. The technology is supposedly easier and cheaper to manufacture than OLED and claims to improve the reproduction rate of colour of conventional LCD/LED sets by up to 30 per cent.

Samsung used Quantum Dot in its 2016 range of SUHD screens - both the UE55KS7000 and UE55KS9000 proved excellent in our tests. However, it has also put the technology to a new and interesting use in the form of QLED TVs, which promise all the benefits of OLED for a fraction of the price. For more, read our in-depth feature on QLED TV.

LG previously promised a 4K Quantum Dot TV, although we're yet to see it, and TCL released one in the US, adding it would be coming to Europe.

But Quantum Dot isn't the only rival to OLED. Chinese manufacurer Hisense has introduced its own ULED (Ultra LED) technology, which it claims can produce a picture quality as good as OLED but again for much cheaper. The 65XT910 is subsequently the world's first ULED available to buy for £2200. Although it didn't get the greatest review when it passed through our doors...

MORE: OLED, 4K, 8K TV - the future of TV

Best OLED TVs

LG OLED55B6V

Tested at £2700 / Now £2000 at Sevenoaks and Amazon

This is one of the most affordable 4K OLED TVs around - it's still not cheap, but you get a lot for your money.

LG OLED55B6V review

 

LG OLED65G6V

Tested at £6000 / Now £4400 at various retailers

The G6V is the flagship LG 4K OLED TV for 2016. It combines a stunning picture with an impressive built-in soundbase. But all that TV comes at a very high price...

LG OLED65G6V review

 

LG OLED65E6V

Tested at £5000 / Now £3500 at various retailers

...so you could save yourself a bundle on what is essentially the same screen as the G6, but with a slightly smaller soundbase. It would be our pick for sure.

MORE: LG OLED65E6V review

 

Panasonic TX-65CZ952B

Tested at £8000 

This Pansonic set is incredibly expensive and you'll need a very wide rack, but the picture quality is quite simply jaw-dropping.

Panasonic TX-65CZ952B review

 

MORE: Best TVs 2017

MORE: The future of TV: 10 tech steps to TV heaven