Subpixel rendering

Subpixel rendering is a way to increase the apparent resolution of a computer's liquid crystal display (LCD) or organic light-emitting diode (OLED) display by rendering pixels to take into account the screen type's physical properties. It takes advantage of the fact that each pixel on a colour LCD is actually composed of individual red, green, and blue or other color subpixels to anti-alias text with greater detail or to increase the resolution of all image types on layouts which are specifically designed to be compatible with subpixel rendering.

A single pixel on a colour subpixelated display is made of several colour primaries, typically three coloured elements—ordered (on various displays) either as blue, green, and red (BGR), or as red, green, and blue (RGB). Some displays have more than three primaries, often called MultiPrimary, such as the combination of red, green, blue, and yellow (RGBY), or red, green, blue and white (RGBW), or even red, green, blue, yellow, and cyan (RGBYC).

These pixel components, sometimes called subpixels, appear as a single colour to the human eye because of blurring by the optics and spatial integration by nerve cells in the eye. The components are easily visible, however, when viewed with a small magnifying glass, such as a loupe. Over a certain resolution threshold the colours in the subpixels are not visible, but the relative intensity of the components shifts the apparent position or orientation of a line.

Subpixel rendering is better suited to some display technologies than others. The technology is well-suited to LCDs and other technologies where each logical pixel corresponds directly to three or more independent coloured subpixels, but less so for CRTs.

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