Henan Toda Technology Co., Ltd. , https://www.todafurniture.com[Abstract] The color coordinates and color difference formulas of CIE 1964 supplementary standard chromaticity system, CIE 1976 (L * a * b *) color space and the correlation between light and color Theoretical analysis analyzes the color measurement requirements of profiles in GB / T 8814-2004 "Unplasticized Polyvinyl Chloride (PVC-U) Profiles for Doors and Windows", and gives the conversion of gray card series and total color difference relationship.