What is OLED?

OLED TV is one of the most exciting breakthroughs in flat screen displays in recent years. But with several different display technologies vying for the attention of consumers, what exactly is OLED and what makes it so different from other display technologies?

OLED stands for Organic Light-Emitting Diode. You may be familiar with LED technology. The “O” in OLED stands for organic. This refers to the organic compounds, such as carbon, that emit light in response to an electric current. It marks a significant departure from other LED panels in one significant way: the source of the light.

A photograph of an LG OLED TV

Earlier LED/LCD panels used an LED backlight to illuminate the pixels of an LCD (Liquid Crystal Display) panel. This backlighting came in three different forms. Edge-lit LED illuminated the screen from the top, bottom, or sides. Direct-lit provided illumination from behind the LCD panel. The latest technology, full-array, introduced a full panel of dimmable LEDs in the back of the set for more light control across the screen.

In OLED TVs, there is no need for any backlight. Each tiny LED in an OLED display creates its own light. The emissive LED technology in OLED creates a host of advantages for consumers.

How are they made?

An OLED screen has six layers that work together to produce colour images. These layers include the following, from bottom to top:

Substrate – the foundation structure that supports the panel. This is typically made out of glass or plastic
Anode – a transparent layer that removes electrons when electrical current flows through it
Conductive Layer – contains organic molecules or polymers such as polyaniline that transfer current to the emissive layer
Emissive Layer – contains organic molecules or polymers that light up when current is passed through them
Cathode – injects electrons into the other layers when current flows through it
Cover – the top protective layer of the screen. This is typically made out of glass or plastic

OLED Structure

Advantages of OLED over LCD

  • Screens can be significantly thinner, resulting in lighter weight
  • Has better contrast and allows a higher refresh rate
  • Allows new display capabilities like ultra-thin, transparent displays
  • Low power consumption
  • OLED-based screens provide a fuller viewing angle and are also much brighter
  • Durability is better. OLED screens can work in broader temperatures as well

Uniform Lighting

While manufacturers have continually improved their backlighting technology, it is nearly impossible to light every area of the display with the same intensity. This can lead to noticeable light spots and dark spots across the panel. Because OLED does not rely on a backlight, the brightness can be controlled on a pixel by pixel basis, leading to more uniform lightening.

Contrast

Backlighting technology makes perfect black nearly impossible. Because there is a light shining from the back or sides of the image, pure black is difficult to represent. On an OLED set, any pixel can be switched completely off. Since there is no residual light coming from behind, this will be expressed as the purest black possible. This leads to contrast ratios that are only limited by the maximum brightness of the set.

Refresh Rate

OLED displays offer refresh rates as low as 0.001ms, which is roughly 1000 times faster than standard LED-LCD panels. This smooth performance makes them perfect for gamers and sports enthusiasts.

Viewing Angle

Most higher-end displays look great when you are sitting directly in front of them. Unfortunately, that is not always possible. OLEDs, because there is no backlight, offer vivid color and contrast at much greater viewing angles.

Thickness

Because OLEDs create their own light, there are far fewer components required to produce the picture. This means a drastically thinner screen. The thickness of OLED sets is measured in millimetres and manufacturers are already demonstrating paper-thin sets.

OLED TVs are currently offered by several manufacturers including Sony, LG, Panasonic, and Philips. They currently range in size from 55″ to 77″.

Is OLED Right for You?

OLED represents the latest in flat panel display technology. However, there are still some impressive displays using LED-LCD and the newer QLED. There are several factors to take into account including price, size, and how you will be using your set.