THE LANGUAGE OF DISPLAYS
Term/parameter	Discussion
Artifact	Anything you don't want the viewer to see. When the resolution is too low, pixels are too large, or the viewer is too close to the screen.
Brightness	Expressed in candelas/m2 (or nits).
Contrast ratio	Expressed as a ratio of the brightness of the illuminated region to the nonilluminated region.
Illumination efficiency	A ratio of light-output to power-delivered (in lumens/W).
Maximum viewing angle	Total included angle between the viewer's eye and the plane of the screen—measured along either the X or Y axis—over which a pixel on the screen remains perceptible, with the maximum being 180°. (Often, the maximum viewing angle along the X axis is different than that along the Y axis.)
Optimum viewing distance	This is a rule of thumb; 1 minute of arc (see discussion in the text and Figure 1.)
Pixel density	Expressed in pixels/lineal inch.
Pixelation	A condition when individual pixels become discernible; an artifact.
Resolution	Expressed in pixels—horizontal by vertical—such as 1280 by 1024 pixels (SXGA).