English: The photo illustrates the effect of a polished glass surface (left) and a matte glass surface (right) on the contrast of the visual information when ambient light is reflected in the display. The light source (fluorescent lamp) is distinctly visible on the left and the intensity of refected light is so high that the information hardly can be recognized (disability glare). Outside of the specular direction (i.e. where there is no image of the lamp) the contrast of the etxt is high. On the right side the incident light is scattered about the specular direction, the contrast in the specular direction is reduced, but no distinct image of the lamp is visible and the text can be read without problems. Outside of the specular direction a veiling glare can be observed that is slightly reducing the contrast over an extended area.