Subpixel Rendering - Addressability Vs. Resolution

Addressability Vs. Resolution

With subpixel rendering technology, the number of points that may be independently addressed to reconstruct the image is increased. When the green subpixels are reconstructing the shoulders, the red subpixels are reconstructing near the peaks and vice versa. For text fonts, increasing the addressability allows the font designer to use spatial frequencies and phases that would have created noticeable distortions had it been whole pixel rendered. The improvement is most noted on italic fonts which exhibit different phases on each row. This reduction in moiré distortion is the primary benefit of subpixel rendered fonts on the conventional RGB Stripe panel.

Although subpixel rendering increases the number of reconstruction points on the display this does not always mean that higher resolution, higher spatial frequencies, more lines and spaces, may be displayed on a given arrangement of colour subpixels. A phenomenon occurs as the spatial frequency is increased past the whole pixel Nyquist limit from the Nyquist–Shannon sampling theorem; Chromatic aliasing (colour fringes) may appear with higher spatial frequencies in a given orientation on the colour subpixel arrangement.