Visual System

Understanding how the human visual system functions is essential to designing effective visual displays. Such understanding provides the basis for color selection, text and item size determination, and coding methods. It also helps in the design of displays for all users, including those with color vision deficiencies and acuity problems.

Contrast & Color

Whether using CRT, LCD, or plasma technology, all computer monitor color generation is based on the mixing of the three primaries: red, green, blue. This mimics the color perception of the human visual system which is based on red, green, and blue color receptors. While color can be a powerful means to code information on a display and enhance ease and efficiency of use, luminance contrast is more important than color in determining text, symbol, or item discriminability.

The CIELUV color space can be used to calculate the perceptual distance between colors. The greater this distance, the greater the likelihood that the colors can be easily differentiated on the display. CIELUV can be used to calculate the "gamut" or range of colors that can be produced by a particular monitor, so that color choices can be made. CIELUV is useful in defining other color and luminance properties pertinent to color use in display design and to match colors across displays. CIE color space concepts and calculations should be mastered by anyone specifying colors for an electronic display.