The accurate control and specification of the parameters of color in video display terminals is of increasing concern to a wide range of users who are utilizing multicolor displays as a means of organizing and conveying comprehensive visual information. There are a number of advantages to using color in displays. Recent generations have grown up deriving much of their visual information from color television and, in general, prefer lifelike, multicolor images over single color or black and white images. Also, as an inherent part of human visual perception, color aids in the ability to attract a user's attention, to organize information into logical parts, and to make both qualitative and quantitative distinctions.