The future: OLED and QLED
There are some up-and-coming technologies that are making LED displays even better. OLED and QLED displays are bound to become more commonplace in the future.
“OLED” stands for “organic light-emitting diode.” What makes an OLED unique is that each pixel has a light source that can be individually shut off. On an LED monitor, the only way to keep a pixel from emitting light is to keep the liquid crystal closed. It’s effective, but not perfect - a small portion of light will always seep through. On an OLED monitor, each pixel’s light can be entirely shut off so no light at all will emanate through the liquid crystal. These means you can get truer blacks, which means deeper contrast ratios and better image quality.
There are two additional advantages. First, OLED monitors can be made even thinner than LED monitors because there’s not a separate layer of LEDs behind the pixels. Second, these monitors are more energy efficient because the pixels will only draw power when their light is turned on. One of the downsides, though, is that pixel burn-in will be more noticeable since some pixels will inevitably be used more than others .
“QLED” stands for “quantum light-emitting diode.” In a QLED monitor, each pixel has a “quantum dot.” Quantum dots are tiny phosphor particles that glow when you shine a light upon them .
Why would you need a glowing particle over each pixel? Because LEDs aren’t very good at emitting bright light. The brightest color is white. But an LED doesn’t emit white light – it emits blue light. Each LED is given a yellow phosphor coating to make it appear less blue and more white, but it’s still not true white. The “blueness” of LEDs negatively impacts the red, blue, and green colors on LED displays. LED monitors have automatic features that adjust the RGB colors to compensate for the blue light, but it can’t compensate for the weaker light intensity.
That’s where the quantum dots come in. The pixels are overlayed by a sheet of red and green quantum dots (there is no blue because blue light is already being emitted by the LED). When the light shines through the liquid crystals, the quantum dots glow, and you’re given a bright, vivid, and lovely spectrum of RGB colors.
QLED monitors are capable of creating pictures that are both dynamic and bright, and which have stellar contrast ratios.