The days of thick and clunky display devices are over. Nearly all display devices manufactured today are thin. Known as flat-panel displays, they are used in smartphones, monitors, televisions and other devices with a display. There are several types of flat-panel display technologies, however, each of which works in a different way.
By far, the most common display technology is liquid-crystal display (LCD). LCDs are characterized by the use of liquid pixels sandwiched between two layers of polarizing glass. Behind these two layers is a backlighting system that illuminates the pixels. When illuminated, the pixels create a visible image. How popular are LCDs exactly? In any given year, hundreds of millions of LCD devices are purchased and shipped globally. This makes LCD the most common display technology on the market.
The second-most common display technology is light-emitting diode (LED). Here’s the thing: LED displays are technically LCD displays. They are known as “LEDs” because they use LED backlighting. LED displays still feature liquid pixels between two layers of polarizing glass. The only difference is that they use LED backlighting. Other LCD displays use a different type of backlighting. LED displays, however, specifically use LED backlighting to illuminate the liquid pixels.
Another flat-panel display technology is organic light-emitting diode (OLED). OLED displays are similar to LCD displays. The main difference between the two technologies is that OLEDs produce their own illumination, whereas LCDs use LED backlighting for illumination.
The pixels in an OLED display are capable of producing their own illumination. They don’t require a separate backlighting solution. Instead, each pixel can illuminate itself. This allows for more a diverse range of colors and, ultimately, higher-quality images with greater detail. The downside to OLEDs is that they typically cost more than their LCD counterparts.
Finally, electroluminescent (EL) is a type of flat-panel display technology. EL displays receive their namesake from their use of an electroluminescent material. The electroluminescent material is placed between two conductive layers. When a current is applied to the layers, the material produced illumination, thereby creating a visible image.
Like OLED displays, EL displays don’t require a separate backlighting solution. They are able to produce their own illumination thanks to their use of an electroluminescent material. Electroluminescent material, such as GaAs, glows when an electrical current runs through it. EL displays leverage this phenomenon to produce illumination.