OLED or LED - which is the best choice? We compared the display technologies and tell you which display panel is right for you!
It is probably the biggest revolution in the display sector since the first LCD monitor: Self-illuminating OLED displays ensure perfect black, bright colors, and extremely fast response times.
IPS: The better alternative to LED
IPS panels (IPS stands for “In-Plane Switching”) are also based on the LCD standard. However, the electrode gate responsible for polarization is thinner. As a result, the viewing angle stability is significantly better in comparison, you can actually see a color-true image from any angle. That is why even many high-priced smartphones rely on an IPS panel.
The IPS technology is also used primarily in the professional sector for computer displays. People who need good color rendering swear by IPS technology.
However, IPS panels have two disadvantages: On the one hand, the background lighting has to be stronger in order to achieve the same brightness as TFT displays. This increases power consumption by a few percent. On the other hand, IPS displays react a little more slowly than normal displays.
How does IPS technology work?
The principle of IPS technology is based on the polarization of light. Nowadays, most TFT displays are built using TN technology (twisted nematic), in which the liquid crystals twist according to voltages applied to them. However, in TN technology, the colors only appear bright when you look at the display head-on.
IPS panels do not use twisted nematic cells but rather a horizontally aligned film with liquid crystal molecules in vertical alignment. This means they react more quickly and offer an improved color reproduction performance. How fast does it work? Theoretically up to 662 Hz! That's right, that’s how many times per second for example for movies or games with extremely fast motion effects can be rendered
In-Plane Switching (IPS) displays provide very accurate colors and high contrast, even at an angle. Due to the IPS technology, the images appear virtually true from every position.
How does LED technology work?
An LED display is a matrix of light-emitting diodes, also called LEDs. In an LCD, these are used as individual pixels that can be turned on and off. They emit a red, green or blue color depending on their construction. By combining the three colors via various eye patterns it is possible to produce other colors.
LED displays have become popular because they offer good image quality at extremely low power consumption compared to TFT technology which has been widespread up until now.
LED technology must be particularly efficient because it has no back-light and thus consumes no energy when not required - i.e., during dark scenes in a movie or while playing games that don't require any visual feedback.
How does OLED technology work?
OLED technology is characterized by the fact that it is self-illuminating. The individual pixels are not backlit but they emit their own light. This makes the display extremely thin, thereby minimizing power consumption.
However, OLEDs can only be built in small sizes so far and this will likely remain a limitation for some time to come due to technological problems. When you put standard RGB (Red/Green/Blue) OLEDs together, there is no such thing as color purity. In other words: Only a few of these pixels produce true colors.
Therefore manufacturers currently produce RGBW panels that use white pixels instead of red or blue ones and then mix the colors optically with special diodes – a method called de-fringing. This enables very bright colors combined with an extremely high contrast ratio of over 5,000:1. Due to these features, OLED panels are well suited for use in smartphones or other small devices.
Battery consumption depends on the display type used. For example, a TFT display uses around 30% more energy than an LED one due to the power needed for back-lighting. However, IPS technology differentiates itself only slightly from TN displays by adding 3 or 4 percent more consumption per unit surface area and this is negligible.
While a conventional display is basically nothing more than a kind of filter that allows the light of a permanently active (LED) backlight to pass through each pixel with a defined intensity and color, the pixels of an OLED display light up themselves. This has several advantages with himself:
- Black parts of the picture have no residual brightness
- The darker the picture, the lower the power consumption
- Extremely stable viewing angles
- Very high color gamut
- Short response times
- Slim design due to the lack of backlighting
As always, there is a catch here too - in this case, we even see four potential problem areas in OLED technology:
- Limited maximum brightness
- High manufacturing costs
- Susceptibility to burn-in
- Aging behavior
Brightness and illumination: IPS vs. OLED
As already briefly indicated, the background lighting of an IPS display always works with constant luminosity regardless of the image content. As a result, the brightness of a white surface is always identical, regardless of whether it covers the entire image or only a very small part of it.
An OLED display typically behaves differently: Since all sub-pixels have to shine with maximum luminosity in a bright, white picture, the power consumption in such a scenario shoots up rapidly.
In order to limit the consumption to an acceptable level and at the same time to extend the life expectancy of the panel (which strongly depends on temperature and brightness), most manufacturers limit the luminance depending on the displayed image content.
To be more precise: The OLED display switches off completely in a dark scene, which can lead to an image that looks less bright. In the practical test, we measured this at around 15 cd/m² instead of the usual 300 or 500 cd/m².
Commercial use of OLED displays is therefore only feasible if they are installed permanently in a fixed location where it doesn't matter too much whether there is always perfect illumination.
But if you want to move your device from indoors to outdoors or vice versa, you have to live with strong changes in brightness and - depending on the weather conditions - may be blurry screen contents due to sunlight being reflected by the light-sensitive display surface.
An additional problem arises when displaying video material in dark scenes.
Contrast and viewing angle stability: IPS vs.OLED
Even with a high-quality IPS panel, black surfaces shine with around a thousandth of the luminance of the backlight - with a brightness of 300 cd / m² this is therefore around 0.3 cd / m². The OLED display, on the other hand, is in a completely different league and is advertised by the manufacturer with a contrast ratio of 2,000,000: 1.
This results in a black value of just 0.00015 cd / m², which can neither be subjectively confirmed nor recorded by measurement - even in a completely darkened room, black is simply black, even with maximum image brightness. But how is it then possible to create a bright picture on such a dark background?
As already mentioned, the OLED display only lights up individual pixels when necessary. The phosphor of each sub-pixel emits light only when struck by an electron beam from behind.
In a classic TV, all three electrons in a highly focused beam must hit the same pixel in order for it to emit light. This means that if you have a black area consisting of 9 x 5 pixels (45), there are 345 electron beams that can potentially arrive at the screen surface - but at most 3 can strike the same pixel.
First of all, it is important to understand what this difference entails for OLED displays in general: If you represent pure black with 5% brightness on a regular IPS display, there is always 95 % of the entire backlight that are unused - only 5 % are used to produce precisely this 5 % brightness.
On an OLED display with multiple sub-pixels however, each individual sub-pixel can be switched completely off when displaying pure black - resulting in 0% brightness and better contrast in dark picture areas! As already mentioned, this difference cannot be copied by LED or LCD technology in any way.
OLED panels are much more expensive than the alternatives due to the sophisticated manufacturing technology needed. This is why you can currently purchase an Asus Designo Curve MX38VC, which features an IPS panel with 1080p resolution for just over 450 Euros (~$463) - while Samsung's own UE590 UHD monitor sells for just below 1,300 Euros (~$1331).
The latter even features a 14-bit 3D LUT, something that normal users won't benefit from at all but which can help calibrate the monitor if required. Of course, there are many other factors to consider when choosing a monitor because both technologies have their own strengths and weaknesses.
IPS + LED displays are already more expensive than OLED, but the average price of an OLED TV with a diagonal of 55 "is currently around 2,000 Euro (~$2700). For comparison: A 55" UHD TV from Samsung is available for around 1,500 Euros (~$2200) and a model from LG can be found for about 1,600 euros (~$2350).
With any high-end panel, you don't have to worry about incorrect colors. Every provider relies on IPS or OLED technology, so you will always see a good picture. However, if you are into particularly high-contrast colors and deep blackness in dark film scenes, there is no way around an OLED screen.
From a price perspective, you should not worry about OLED either.
Most people would benefit more from using an external device to display their content on a larger screen however: A good alternative would be one of the many HDMI-connected PC monitors. Just make sure to select one with an IPS panel, otherwise, you'll have to give up on accurate colors.