What is OLED? A guide to the display technology

OLED displays have grown in popularity over the last decade, featuring in TVs, portable game consoles and smartphones from some of the biggest brands in the tech industry.

We’ll explain what an OLED display is, why it’s become so popular, what makes it better than the alternatives, as well as the disadvantages that you should know about.

What is OLED?

OLED stands for organic light-emitting diode. What’s an organic light-emitting diode? Simply put, it is a light source that’s used in a wider variety of electronics.

What makes OLED different from LED is the organic part, which is a thin film of organic compound that emits light when an electrical current is passed through it.

Manufacturers take this organic semiconducting material and place it between two electrodes, which provides the current. Usually, one of these electrodes is transparent, so the light that is generated can escape and be viewed, by you, on the screen.

Where can I find OLED displays?

OLED is used in a variety of devices. You’ll find it in flexible and transparent displays, to TVs, smartphones, laptops, smartwatches and handheld game consoles.

OLED TVs have been around since 2015, and LG is the biggest producers of OLED screens for TVs. Almost ever single screen in a Panasonic, Sony, Hisense, and Philips TV will have been sourced from LG. Even Samsung uses LG’s OLED for its 83-inch OLED TVs.

QD-OLED is a new form of OLED that compete with LG’s traditional WRGB OLED screens. They’re made by Samsung Display and seek to offer higher brightness and better colour volume than OLED screens.

When it comes to mobile devices, AMOLED is used. AMOLED uses OLED pixels that have thin strips of thin-film-transistors behind them. This layer moves the electric current quicker, creating a more reactive display that’s good for fast moving applications such as video and gaming. Even tiny devices like the Apple Watch Series have AMOLED displays that can hit a rather mental 1000 nits of peak brightness.

The PlayStation Vita had an OLED screen back (and a very nice one too), while the Nintendo Switch OLED has taken on the reins with its latest iteration. Apple’s iPhones have shifted over to OLED, and you’ll find them across most Android smartphones. Laptops also feature the display, such as the Dell XPS 13 OLED and a few Lenovo models.

What makes OLED so good?

In the past, smartphones and televisions used LCD displays, which stands for liquid-crystal display (you can read more about them here). These liquid crystals don’t emit light directly, as they require a backlight to shine through them to create the light.

The key advantage of OLED is that the screen is self-emissive – as in it emits its own light.

No backlight is needed, and because there isn’t an extra layer in the screen, the display can be slimmer. This works to good effect for smartphones, laptops and TVs as the design is thinner, so you can have a screen that can fit into pocket better, or a TV that can sit flush to the wall and not weigh as much.

Other advantages include perfect blacks. LCD screens with a backlight find it difficult to display true blacks because the backlight is always on, leading to leakage of light to the screen. Dimming zones can assist in creating more precise brightness and stronger blacks, but they’re not always perfect.

As OLED screen can dim its screen on a pixel-by-pixel basis, it’s able to turn on and off every pixel. If it needs to display black in an area, all it needs to do is switch the pixel off to stop light from coming through.

Perfect blacks also allow for infinite contrast, so the difference between the darkest and brightest parts of the image is higher than nearly any other display. This makes for richer, more dynamic image and great if you watch films.

OLED is capable of wider angles because of its self-emissive screen, too. With TVs, you can sit more to the sides and get a similar colour performance and level of contrast as you would if you were sitting in front of it. With LCD/LED TVs, moving too far to the side can lead to a reduction in contrast, washed-out colours and blooming (that’s a ring of light around bright objects).

As a material OLED is more flexible than LCD or LED, and this extends the number of uses for it. You can get curved and rollable OLED displays, such as the LG OLED R rollable TV; and you’ll see flexible displays in mobile devices with the increasing popularity of foldable phones and tablets such as the Microsoft Surface Duo and Samsung Galaxy Z Fold3, both of which use flexible AMOLED (Active-Matrix Organic Light Emitting Diode) display.

Transparent OLEDs screens are making the mark, so you can both see the screen and see through it.

Energy consumption is also less hungry as result of not needing a backlight to produce light. That makes them a good choice for smaller devices as they can last a little longer than their LCD-based equivalents. However, higher resolution OLED screens can reduce battery life because of the extra number of pixels causes a drain on the battery.

What are the disadvantages of OLED?

In the TV world, OLEDs can’t go as consistently bright as LCDs. The comparative lack of brightness means that LCD LED TVs (such as QLED and Mini LED) can produce a punchier, brighter and vibrant HDR performance. That said, there is new technology such as LG Display’s Micro Lens Array panel that can produce brightness up 1700 nits. This has so far been reserved for the premium TV models such as the LG G3 OLED, Panasonic MZ2000, and Philips OLED+908.

QD-OLED can also achieve higher peak luminance levels and even better viewing angles, more accurate colours and better HDR performance. Currently, only Samsung and Sony have launched QD-OLED TVs.

OLED also suffers from an issue called imaged retention, and a more severe problem called burn-in. This happens when static elements – logos, news tickers – are displayed continuously over extended periods of time or images that are repeated over and over. The result is a residual image – a ghost image – that can be either temporary (image retention) or more permanent (burn-in).

With normal use image retention shouldn’t be an issue. It’s only when an OLED TVs are used out of their normal parameters does it become a potential problem. Manufacturers have implemented solutions to keep image retention/burn-in at bay, such as pixel shifting (which moves the pixels on the screen), employing screensavers and reducing the brightness in areas of the screen where logos and static elements are detected.

Use an OLED display as you normally would, and the probability of image retention is low. However, other types of display such as LCD LED are free from this problem.

Another disadvantage is that OLED displays don’t last as long as others. As OLED uses organic material, it degrades over time, causing the picture performance to deteriorate (colour balance will change over time). There’s no need to worry about this in the short-term, as it should take many, many years for this to occur.

Water can damage OLED screens, which will affect mobile devices. You’ll want to keep an AMOLED screen away from any water (and preferably in a case).

OLEDs have been more expensive to produce, although the cost has come down. While not inexpensive to make, however, it remains a relatively pricey process.

Depending on your market, you can get OLED TVs for less than £1000, and a phone for less than £199 – a far cry from several years ago.

One final con is that OLED works best in low-light conditions as bright lights shining directly on the screen can affect its contrast. Samsung’s Super AMOLED has made steps forward in this regard, deflecting sunlight so the screen can be easier to read, and increased brightness helps to in reducing this effect.

Should you buy an OLED display?

In our view, the pros of OLED outweigh the cons. It is improving and getting more affordable at the same time. The contrast and black level performance is superior to any other display whether it’s a conventional OLED or QD-OLED, resulting in a richer, impactful performance.

The fast refresh rates make them excellent for gaming, and that also allows to be more fluid when handling motion, so there is less motion blur and fewer artifacts such as judder and stutter from sports that you can get with LCD LED.

There are disadvantages to consider too. The lack of brightness relative to LCD as well as image retention and deterioration over time. The former is less likely to be an issue with general use and the latter will occur over a lengthy period of time.

There is less to worry about OLED’s issues than a few years ago, though it remains an expensive option. Nevertheless, OLED offers some of the best images around.

Whether it’s a TV, mobile device, or gaming device, it’s worth investing in an OLED display. The future looks to be getting brighter. Quite literally.