An Introduction to the Types of Display Technology
It’s no secret that we live in a screen-focused society. Smartphones, tablets, laptops, televisions, and even some advertisements such as those found in shopping centres all use display technology. Everyone is likely to encounter some form of display each day.
Our daily exposure to screens means we often take this technology for granted, but they do not all use the same components; rather, different types of display technologies are used depending on the purpose of the display. Here’s an introduction to the different types of display technology.
LCD (liquid crystal display)
LCDs are often used for television screens and computer monitors. They are made from several layers; a layer of liquid crystal is pressed between a sheet of glass substrate formed with transparent pixel electrodes and TFTs (thin-film transistors) and a sheet of substrate with a colour filter and transparent counter electrodes. LCD technology doesn’t emit light, rather it blocks light to create a picture on the screen, so they need a source of backlighting.
TVs originally used CCFLs (cold cathode fluorescent lamps) for their backlighting. However, because LED technology is now superior in terms of brightness output, compactness, and energy efficiency, modern LCD screens use LEDs for their backlighting.
LED (light-emitting diode), OLED (organic light emitting-diode) and AMOLED (active-matrix organic light-emitting diode)
LED screens are composed of many LEDs placed close together to form a display panel. The LEDs in these displays usually emit only three colours, (red, green and blue) but these can be combined to make most colours in the visible spectrum.
OLEDs are the next generation of technology to be used in place of LCD and regular LED displays. AMOLEDs are even more advanced, using active-matrix technology to provide a superior picture – these are used in smartphone displays.
LED screens can be used for any kind of display, such as signs or any outdoor screens. They will use less energy to operate, whilst still being extremely bright and retaining a high picture quality and clarity. Large display screens such as those found in Times Square and Piccadilly Circus use LED displays because they do not get washed out by ambient light. Because of the panel makeup of LED displays, the size of screens can be increased without compromising on picture quality.
ELD (electroluminescent display)
Electroluminescent displays are flat panel technologies that are created by a layer of electroluminescent material pressed between two layers of conductors. When a current flows through the display, the electroluminescent material produces radiation that appears as visible light. Electroluminescent displays can be paper-thin and operate in more extreme temperatures than other light sources.
ELDs are typically used for the displays in automobiles and on audio devices and to illuminate keypads and watch dials, as well as larger applications such as graphics on bus stops, reception desks and vending machines.
PDP (plasma display panels)
Plasma displays use plasma, an electronically-charged ionized gas, to create a picture. Plasma displays originally replaced CRT (cathode ray tube) TVs because the sets could be made much thinner. Plasma displays often have a wider viewing angle, brighter colours and deeper blacks than those provided by LCDs.
Plasma displays aren’t seen much anymore; they were once the best type of display available when it came to TV sets but have since been outstripped significantly for that purpose by OLEDs.
QLED (quantum dot light emitting diode)
QLED technology uses a metallic quantum dot filter to enhance colour and contrast. This dot filter is a film of crystal semiconductor particles that replaces the RGB filters used in older TVs and can be controlled to change their colour output. Currently, QLEDs can produce the highest level of brightness, the largest colour palette, and the purest whites.
Whilst the quantum dot filter technology is new to the world of screens, this type of display is an advancement on existing LED/LCD tech, and still requires the use of backlighting. Therefore, the main competitor for QLED is OLED, which produces its own light.
There are a lot of bold claims about what type of display gives the ‘best picture quality’ but a lot of it depends on what you are manufacturing. Hopefully, this introduction to the types of display technology has been useful in understanding the differences.
You can take a look at our range of displays here.
