A Quantum Dot is a human-made nanoparticle that has semiconductor properties. They’re tiny, ranging in size from two to 10 nanometers, with the size of the particle dictating the wavelength of light it emits, and therefore the color. When Quantum Dots are hit with a light source, each dot emits a color of a specific bandwidth: Larger dots emit light that is skewed toward red, and progressively smaller dots emit light that is skewed more toward green.
Using Quantum Dots means the range of colors and their accuracy is maintained even at peak brightness, while other display technologies like OLED might wash out colors when scenes require full brightness. The result with QLED is accurate, rich and detailed colors on displays, in any light.