Liquid crystal display grid. Light micrograph of part of the grid of subpixels (rectangles) from a liquid crystal display (LCD) screen, with some of them lit up. Pixels are tiny areas of a display screen, comprising 3 subpixels coloured red, green and blue. The underlying grid supplies electricity to the liquid crystals in each subpixel. This affects the optical properties of the liquid crystals, changing the transmission of light through them. The combination of green, blue and red can produce over 16 million shades of colour on the computer's LCD screen. An RGB screen can have millions of subpixels.