OLED vs LED - Advantages and Disadvantages

• • Higher contrast ratio. Because OLEDs emit their light directly to screen, a given grouping of pixels can effectively be completely shut off when instructed to display dark areas. In this state they emit no light at all, resulting in a clear and obvious perception of very deep, rich blacks and tonal shades.

    • Most LCD types - including standard LED panels - can’t manage such impressive contrast ratios, as their version of ‘black’ has to be achieved by simply masking the LED display backlighting to whatever extent is possible.

    • Under these conditions, there’s almost always some degree of backlight bleed from LED displays, and as a result, their blacks are far less deep and crisp.

  • Wider viewing angles. Again, this is because OLEDs are located much closer to the surface and emit their light directly to the screen, without having to pass through a liquid crystal layer as you’d find on standard LED displays.

    • The LCD layer causes a degree of refraction that can have odd effects when viewing a standard LED panel from more acute angles.

    • Higher quality LED panels, such as those that use In-Plane Switching (IPS) technology, can mitigate this to an extent - but cheaper versions such as Twisted Nematic (TN) screens are still common, and do suffer greatly in this area.

  • Quicker response times. Display ‘response times’ refer to the length of time it takes a given pixel to switch between on and off states in response to an input signal.

    • As outlined above, current OLED displays are able to do this in a blink, and can, therefore, boast far better response times than LED/LCD panels - as low as 1 millisecond, in fact.

    • This makes OLEDs the clear winners when it comes to displaying images in rapid motion, with much less noticeable artifacting. LEDs struggle in this regard, due in part to every single diode having to illuminate multiple pixels behind an LCD layer

Potential disadvantages of OLED displays when placed up against LED/LCD versions, however, are as follows:

• • Shorter lifespan. The organic materials used in the OLEDs have a limited lifespan compared to LCD displays

  • Lower brightness. While the contrast ratio is far superior on a typical OLED display, its overall luminosity level - generally measured in ‘nits’, which roughly equates to candles per square metre - is considerably lower due to the organic nature of the molecules at its core.

    • This isn’t a huge disadvantage in some scenarios, especially as both display types can get plenty bright enough for standard indoor viewing, but it’s a potential problem when it comes to comparative outdoor performance (such as is often required in phones and other handheld devices).

    • In high-exposure conditions, OLEDs can appear washed out and difficult to read, or struggle to achieve sufficiently accurate, rich colour reproduction. Increasing overall screen brightness to combat these issues can be effective, but can also further reduce the lifespan of OLED displays.

  • Higher power consumption. One of the real advantages of LED technology is the very low power draw it requires to run bright, crisp illumination for extended periods.

    • An OLED display can also achieve this to an extent, but in so doing it will generally consume significantly more power than an equivalent LCD display (unless the image is primarily black, for reasons outlined above).

  • Possibility of burn-in over time. Although on paper it should be difficult to achieve given the (still relatively low) power consumption of OLED displays, some early adopters of the technology have reported issues with overuse of specific pixels leading to prematurely faded areas on the screen.

    • In extreme cases, this can lead to a ‘ghost’ image being permanently and indelibly overlaid on top of whatever else the screen is trying to display, as the pixels in that area have degraded.