Pentile HD Display
Like the previous high-end Samsung smartphones, the Galaxy S3 comes with a Super AMOLED display. Compared to the S2, the screen has grown quite a bit, from 4.3 inches to 4.8 inches. It's also more elongated and has more pixels, 1280x720 to be exact.
However, there is one area in which the new screen is inferior to that of its predecessor. The Super AMOLED HD display on the Galaxy S3 has a pentile pixel matrix, while the S2 has an RGB matrix. In an RGB matrix each pixel consists of a red, green and blue subpixel, which can be mixed into every conceivable colour. In a pentile matrix each pixel has a green subpixel, but the red and blue subpixels alternate per pixel. This only requires two-thirds as many subpixels, but the rendering accuracy and image sharpness suffer somewhat.
For the Galaxy S III Samsung opted for a pentile matrix display, like on the Galaxy S1 and the Note. It probably has to do with production costs, but Samsung also declared that the choice for pentile was made because the lifespan of blue subpixels is shorter than that of the red and green ones. In a standard RGB matrix all three subpixels are the same size, which means that the colour rendering will change as time passes. In a pentile matrix the blue subpixels are significantly larger than the red and green ones, which Samsung claims will better counteract the aging process.
To that we can add that with a very high pixel density such as the 306 ppi of the Samsung Galaxy S III the decreased image sharpness of a pentile matrix is much less noticeable than at lower resolutions. How this impacts real-life performance, you can read on the next page.