LCD stands for liquid crystal display, and it is one of the most power-efficient display technologies developed to date. Such displays use the light-modulating properties of liquid crystalline compounds.
The structure of an LCD is complex, but the basic principle is that each crystal acts as a shutter, letting light pass through or blocking it. In front of the liquid crystal layer, there is a color filter with a matrix of pixels. Each pixel in the display is made of three subpixels (red, green, and blue). By quickly switching pixels on and off, different colors are reproduced. Since these displays work by blocking light rather than actively emitting light, they consume less power than the traditional LED or CRT displays. LG Electronics has experimented with four-subpixel LCD panels (adding a white subpixel), but this subpixel arrangement has not been successful in achieving UHD resolution.
Unlike other popular display technologies such as OLED or AMOLED, LCDs have three subpixels for each of its pixels, rendering sharper images. Thanks to color filters, these pixels produce red, green, and blue hues, which, controlled across the liquid crystal layer that gives the display its name, are able to present a broad spectrum of colors.
One of the significant advantages of LCDs is the feasibility of applying it to devices of diverse shapes and sizes, from wearables to mobile devices and large TVs. Despite its positives, however, LCDs have considerable drawbacks, due to which OLED is becoming a favored display technology. Some of the shortcomings of LCDs are a potential ghosting effect with fast-moving images, poor reproduction of black tones, limited brightness, and a restricted viewing angle.