... observerson the basis of ability to see,and it reflects the standardS scope of color ... applied to quality control of plastic and printing industriesDisplay directly color difference by E*abL*a*bCIE_L* ... Workin~theory Compa re the color difference between sample and the measured subject thenoutput CIE_Lab 3 groups ... ,and the 4 groups of E,L,a,b data aftercomparisionE stands for the totaI color difference ...