ΔE (Delta E) is an internationally standardized unit of measurement for total color difference and a core benchmark for judging the accuracy of color reproduction and color matching.

The human eye has inherent limitations in its ability to distinguish colors, while professional spectrophotometers can capture minute color differences that are completely imperceptible to the human eye, accurately quantifying color deviations and providing scientific and objective data support for industrial color matching, quality control, and mass production with consistent color.