Also called phosphor pitch, a measurement that indicates the diagonal distance between like-colored phosphor dots on a display screen. Measured in millimeters, the dot pitch is one of the principal characteristics that determines the quality of display monitors. The lower the number, the crisper the image. The dot pitch of color monitors for personal computers ranges from about 0.15 mm to 0.30 mm.
CRT Characteristics Describes analog and Digital CRTs, dot pitch, shadow mask and aperture grill, image quality factors, and magnetization and degaussing. This page is from "The PC Guide."